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Item #:
90617567
OA-991ES Plus Scientific Calculator with Natural Formula Visualization Display 417 Functions Dual Power & Lightweight Design for High School Students
Item #:
90617567
AUD 47
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Imported from USA store
QTY:
Order now and get it around Tuesday, July 21
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Complies with STEM-approved standards with exam-mode features that disable advanced functions—trusted by educators for standardized test prep.
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What Stands Out
Natural Formula Display
Visualize complex formulas effortlessly with the natural display feature, enhancing understanding and learning for students and teachers alike.
Dual Power System
Utilizes both solar and battery power to ensure reliability and longevity, making it ideal for extensive use in classrooms and beyond.
Lightweight Design
Designed for portability, the lightweight structure makes it easy for students to carry in backpacks, ensuring they always have the tools they need for success.
Product Details
- 【Exam Compliance】Complies with STEM-approved standards with exam-mode features that disable advanced functions (local policies may vary). Includes anti-cheating design and clear exam-mode instructions—trusted by educators for standardized test prep.
- 【Natural Formula Visualization】Displays fractions, integrals, and equations in a Classroom-standard format. Step-by-step tracking helps students understand problem-solving logic, while teachers can demonstrate derivative calculations from four perspectives.
- 【417 Calculation Functions】Engineered for STEM curricula, supporting matrix operations (up to 4x4), vector calculations, 40 metric conversions, and 9 variable memories. Ideal for use in schools, offices, and business, meeting the needs of various fields.
- 【Professional-Grade Durability】Shock-resistant design with a 3-layer protective case (scratch-resistant screen, reinforced buttons, and impact-absorbing frame). Dual power (solar/LR44) enhances energy efficiency—built to withstand daily classroom use and backpack tosses.
- 【Ergonomic Learning System】Reduces neck strain during extended use. Features a variety of function keys to simplify complex calculations, including the ‘S-D’ button for toggling between fractions and decimals, making exact value calculations effortless.
| Calculator Type | Engineering/Scientific |
| Power Source | Solar Powered |
| Screen Size | 2.5 Inches (6.4 cm) |
| Number of Batteries | 1 LR44 batteries required. (included) |
| Display Type | LCD |
| Color | black |
| Enclosure Material | Plastic |
| Item Dimensions L x W | 6.5"L x 3.15"W (16.5 cm) |
| Brand | DUPOTA |
| Model Name | OA-991ES Plus |
| UPC | 726434206862 |
| Manufacturer | DUPOTA CO.,LTD. |
| Mfr Part Number | OA-991ES PLUS-XY |
| Model Number | OA-991ES Plus |
| Item Weight | 125 Grams |
| Unit Count | 1.0 Count |
Who Should Buy?
-
High School Students
Ideal for students needing advanced calculations and formula visualization for subjects like math, physics, and chemistry.
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Teachers
Useful for educators demonstrating complex equations and concepts in a clear, visual format during lessons.
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STEM Enthusiasts
Great for individuals engaged in science, technology, engineering, or math, requiring extensive functions for diverse calculations.
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Casual Users
Not ideal for those who only need basic calculations or infrequent usage of advanced mathematical functions.
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Professional Engineers
May not meet the complex needs of engineering professionals requiring advanced programming or graphing capabilities.
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Very Young Students
Not best suited for young beginners who might find more straightforward calculators easier to understand and use.
Product Description
Have any Query? Chat with us
Customer Questions & Answers
-
Question:
What types of functions does the OA-991EX Plus Scientific Calculator support?
Answer: The OA-991EX Plus supports 552 functions including basic arithmetic, trigonometric functions, statistical calculations, and advanced mathematical operations like calculus and complex number calculations. This extensive range of functions makes it ideal for middle and high school students tackling various math subjects such as algebra, geometry, and statistics. Whether you're solving equations or graphing functions, it can accommodate a wide range of educational needs. -
Question:
Is the display on the OA-991EX Plus easy to read?
Answer: Yes, the OA-991EX Plus features a 2-line display that can show up to 102 digits, making it easy to read and follow calculations. This dual-line layout allows users to see the input and results simultaneously, reducing errors and enhancing learning. Students benefit from the clarity, particularly when working on complex equations where visibility matters. -
Question:
What power sources does the OA-991EX Plus use?
Answer: The OA-991EX Plus operates on both solar power and a battery backup, ensuring it remains functional in various lighting conditions. The solar panel serves as the primary power source, while the battery acts as a backup for low light situations, making it reliable for outdoor or dimly lit study environments. This dual-source feature is particularly advantageous for students who may study in varying locations. -
Question:
How does the OA-991EX Plus help with statistics?
Answer: The OA-991EX Plus includes specialized functions for statistical calculations, such as mean, median, variance, and standard deviation. These capabilities help students analyze data sets effectively, making it an essential tool in subjects like statistics and data analysis. This is especially useful when presenting data for class projects or preparing for exams, where understanding data trends is crucial. -
Question:
Is the OA-991EX Plus suitable for advanced math courses?
Answer: Absolutely, the OA-991EX Plus is designed to accommodate advanced math courses, including calculus and higher-level algebra. With its ability to perform complex calculations and graph equations, it supports learning for students aiming for higher education in STEM fields. Students preparing for standardized tests or advanced classes will find it an invaluable asset. -
Question:
What educational level is the OA-991EX Plus best suited for?
Answer: The OA-991EX Plus is ideal for middle to high school students. Its extensive functionalities cater to students who require robust tools for their math and science classes. As students progress through their education, the calculator grows with them, supporting increasingly complex topics encountered in secondary education. -
Question:
Can the OA-991EX Plus handle complex numbers?
Answer: Yes, the OA-991EX Plus can perform calculations involving complex numbers. This is beneficial for students studying advanced mathematics or engineering disciplines where complex number operations are prevalent. By enabling operations such as addition, subtraction, and multiplication of complex numbers, it prepares students for higher education concepts. -
Question:
Does the OA-991EX Plus have graphing capabilities?
Answer: The OA-991EX Plus does not feature advanced graphing capabilities like some graphing calculators; however, it can still handle basic graphing functions. Users can plot simple functions and visualize mathematical relationships. This feature aids students in grasping core concepts in precalculus and trigonometry. -
Question:
What advantages does the solar-powered aspect of the OA-991EX Plus provide?
Answer: The solar-powered feature of the OA-991EX Plus reduces the need for battery replacements, thus offering convenience and environmental benefits. Students can use it without worrying about running out of power during study sessions, ensuring that their learning experience is uninterrupted, regardless of where they study. -
Question:
Where can I buy the OA-991EX Plus Scientific Calculator in Australia?
Answer: You can purchase the OA-991EX Plus Scientific Calculator at Ubuy in Australia. Ubuy provides a convenient online shopping experience, allowing you to check availability, make purchases, and access detailed product information from the comfort of your home.
DUPOTA Scientific OA-991ES Plus Editorial Review
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Customer Reviews & Ratings
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AUD 47
Order now and get it around Tuesday, July 21
This item is not restrict in my country.(Please click on above link if this item is not restrict in your country, So our team will review and allow.)
QTY:
Secured transaction
PCI DSS compliant and ISO 27001:2022 certified, with encrypted payments and full buyer protection on every order.
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Features & Benefits
- Compliant with STEM-approved standards for standardized test preparation.
- Includes anti-cheating features and clear exam-mode instructions.
- Offers 417 calculation functions tailored for STEM curricula.
- Shock-resistant design with a triple-layer protective case.
- Dual power sources enhance energy efficiency for daily use.
- Ergonomic design reduces neck strain, simplifying complex calculations.
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