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How to Use a Numerical Calculator?


Many numerical reasoning tests will require you to use a basic or scientific calculator to manipulate a series of numbers. On these calculator exams, you’ll need to know how to quickly and efficiently program numbers into your device. The more familiar you are with the buttons on the calculator, the easier it will be for you to solve the questions.

So, read through our basic job-seeker’s review and practice with our online screening questions to see if you’ve understood the concepts so you’re ready for the assessment center.


How to Use a Calculator in Numerical Psychometric Exams:


Basic Calculators:

If you’re a new graduate, you’ve probably used a basic calculator a thousand times before. You can find these calculators pretty much anywhere, and they’ll come with your four basic functions along with a few other buttons. We’re going to explain these buttons here.

Percent: [%]
You don’t necessarily need the percentage button to calculate percentages, but it can speed up the process and save you a few seconds here and there.

The percentage key helps you add or multiply the percentage of a number to the original number. So, for example, to calculate 12+15% of 12, you could type in the following:

[12][+][15][%] to get an answer of 13.8

Alternatively, you could find a certain percentage of a total by multiplying. For instance, to find 15% of 12, you’d type in:

[12][X][15][%] to get an answer of 1.8

Practice Question #1:
L’Oreal decides to add 25% more shampoo to each of their bottles of shampoo and take away 25% from each of their bottles of conditioner. If they originally contained 20oz. each, then how much will each bottle contain after the change? Use a basic calculator.

**Answers at bottom of page

Square root/powers: [√] [x^2]
The majority of basic calculators will come with a square root sign. The square root button will tell you the square root of a number but not the cubed or fourth root. You’ll have to experiment with the calculator beforehand to figure out whether you have to press the square root button before or after you enter the original number.

By contrast, there is usually no squared function. You can find the square of a number by entering the number and the multiplication symbol followed by the equals sign as follows.

[12] [X] [=]

This will give you 144. However, there is no way to compute exponents without multiplying by each number individually.

Memory Functions: [MR][MC] [M+] [M-]
These memory functions are designed to help save you time. Basic calculators can only display a few numbers at a time. However, by storing a number in the calculator’s memory, you can use it later on without having to write it down. This function is particularly helpful if you’re dealing with irrational decimals or large numbers.

[M+] will store the number displayed on the screen in the calculator’s memory banks for later use.

[M+] will add whatever number is displayed on the screen to the amount in the memory bank.

[M-] will subtract whatever number is displayed on the screen to the amount in the memory bank.

[MC] will clear the memory bank and set it to zero.

**Some calculators only have [MRC] (memory recall). In that case, [MRC] will stand for [M+], and [AC] will clear the memory bank.

Preparation Question #2:
In Mrs. Merlow’s science class, the students received the following test grades.

67, 67, 67, 67, 73, 73, 89, 89, 89, 89, 89, 91, 96, 96, 96

What was the class average?


Scientific Calculators:

Scientific calculators are slightly more advanced. If you’re told to bring a calculator to the test, you should go ahead and bring a scientific calculator. Not only can you store more information at one time, but you’ll be able to perform complex operations more easily.

Brackets: [(] [)]
On a basic calculator, you have to make sure you’re plugging in the correct numbers in the correct order. Scientific calculators, on the other hand, allow you to enter an entire expression all at one time using brackets to separate the different operations. Use these brackets as parentheses to tell the calculator which operations to perform first.

-Fraction-Decimal Conversions: [S-D]
You prefer working in fractions, but the numerical calculation test asks for the answer as a decimal? No problem. Type in the fraction and then hit the [S→D] button to find the equivalent decimal.

Preparation Question #3:

Find 6/7 in decimal form using your calculator only.

-Memory Function:

-[ANS]: This button will recall the answer from the previous calculation


One Final Tip for Pre-Employment Calculator Testing!

Calculators can certainly save you time on aptitude tests. However, be careful to read each question carefully and extract the important information before turning to your calculator. While your calculator can help you with some of the calculations, it can’t solve the problem for you. Make sure that you’re always thinking critically and checking your work even on a calculator test.



    1. lShampoo: [20][+][25%][=] 25
    2. Conditioner: [20][-][25%][=] 15
  1. [67][X][4][=]268 [M+]




  2. [6][/][7][=] 6/7 [S→D] 85714…