Practice for Percentages Questions in Numerical Reasoning Tests

You can’t even walk into a supermarket without seeing percentages everywhere. The truth is, you just can’t escape them. Whether you’re eating at a restaurant or cutting out a coupon, you can bet you’re going to factor a percentage into the calculation.

As it just so happens, you’ll also find percentages on your numerical reasoning aptitude test. This online screening exam will test whether you have the mathematical ability to handle basic numerical tasks while on the job. In this section, we’ll briefly discuss how to calculate percentages and review some of the question types you’ll encounter on the assessment.

What Are Percentages?

A percentage—literally per cent, or out of 100—is a way of representing a fraction or a decimal. It is, essentially, a fraction with 100 as the denominator. Percentages are, quite simply, easier for people to visualise. That is to say that while someone may be able to estimate 7/8, they’ll have a very clear idea of what 87.5% is.

To convert a decimal to a fraction, you’re going to multiply the number by 100. By moving the decimal point twice to the right, you’ll find the percentage. See the examples below for reference:

0.35=35%

0.075=7.5%

2.46=246%

1.00=100%

How to Calculate Percentages:

Calculate Percentage Off/Added:

Percentage tests are most likely going to ask you to perform one of two calculations: percentage added or percentage taken off.

If you’re calculating how much you should pay for gratuity, you’ll be finding the per cent added. That means that you’ll find a percentage of what you paid and pay that amount of money in addition to the principal amount.

So, if you ate a meal that cost £26, and you want to offer 15% for the tip, you would multiply 26*.15 to get 3.9 and then pay £3.90. However, we can simplify this process by substituting 1.15 for .15 to include the original amount. In that case, you’d multiply 26*1.15 to get 29.90, which would be your total.

You might, however, be calculating per cent off. If you’re paying with a coupon, you’ll want to know how to subtract a percentage from the principal amount. Let’s say you have a coupon for 15% off of a movie theatre ticket of £18. You’d multiply 18*.15 to get 2.7 and then subtract £2.70 from the total. However, if you’ve received a coupon for 15% off, you should know that you’re only paying 85%, in which case you could simply multiply 18*.85 to arrive at your final amount right away.

Calculate Percent Increase/Decrease:

Sometimes you’ll have to calculate per cent increase or decrease. Be careful not to use the techniques described above. This is slightly different and therefore requires a different formula. To calculate percentage increase/decrease, you’ll need to use the following formula:

(old-new)/(old) *100

Let’s put this into practice. Imagine Crispy chips decided to cut on costs and offer 15% fewer chips in each bag. If they started with 50g, what is the weight of the bag now?

(50-x)/(50)*100=15

(50-x)/(50)=.15

50-x=7.5

x=42.5g

You can use this same formula for a per cent increase. Simply plug in the values and solve as normal.

Use the Calculator’s Percentage Function:

Don’t feel like calculating a percentage by hand? That’s okay, you can actually have the calculator do it for you. Whether you’re taking a graduate-level exam and need to plug long strings of numbers into the calculator or you’re taking a pre-employment exam and can’t keep all of the numbers in your head, the percentage key [%] will help you.

The percentage key will turn any decimal into a percentage instantly.

.78 [%] =78%

.69 [%] =69%

.43 [%] =43%

Key Words:

If you’re taking a psychometric test, you should know that the test writers will purposefully try to trick you into falling for a question. Sometimes, for instance, they’ll ask for a percentage without actually using the word percentage. Make sure that you keep your eyes peeled for the words “relative change.” This phrase usually implies that the answer will involve a percentage.

Hey job-seekers! Still nervous for your numerical reasoning test? Don’t sweat it! Watch this video to learn some of our favourite numerical reasoning test tips before heading out to the assessment centre.