alleryStart learning →Find the average of $5, 10, 15, 20$ and $25$.
- $12$
- $14$
- $15$
- $17$
Show answer and solution
Correct answer: C. $15$
Sum $= 5+10+15+20+25 = 75$.
Average $= \dfrac{75}{5} = 15$.
Indian Air Force AFCAT II Averages — practice questions
Explore 37 free Averages questions in Indian Air Force AFCAT II Quantitative Aptitude. Open each question or exercise to read its content, reference answers and available explanation.
Practise Averages with Quill →Averages questions and exercises with answers
Showing questions 1–30 of 37.
Find the average of $5, 10, 15, 20$ and $25$.Read the answer and worked solution →What is the average of the first five natural numbers?Read the answer and worked solution →A man covers half of a journey at $40$ km/hr and the other half at $60$ km/hr. Find his average speed for the whole journey.Read the answer and worked solution →The average of $11$ numbers is $50$. If the average of the first six is $49$ and that of the last six is $52$, find the sixth number.Read the answer and worked solution →The average weight of A, B and C is $45$ kg. The average of A and B is $40$ kg, and the average of B and C is $43$ kg. Find B's weight.Read the answer and worked solution →Average, or spread?Read the answer and worked solution →True or false: what an average tells youRead the answer and worked solution →Order the steps: compute a meanRead the answer and worked solution →Averages and spreadRead the answer and worked solution →Complete the contrastRead the answer and worked solution →True or false: reading an average from a reportRead the answer and worked solution →Assertion and reasonRead the answer and worked solution →Uses every value, or only some?Read the answer and worked solution →Two are true, one is notRead the answer and worked solution →Three of these are wrong. Find the one that holds.Read the answer and worked solution →Flip and pair: statistic with its jobRead the answer and worked solution →Tap every measure of central tendencyRead the answer and worked solution →Spot the one that does not belongRead the answer and worked solution →Averages in a data questionRead the answer and worked solution →Complete the meanRead the answer and worked solution →Order the steps: compare two groups by averageRead the answer and worked solution →True or false: averages that misleadRead the answer and worked solution →Which number would you quote?Read the answer and worked solution →Averages in practiceRead the answer and worked solution →Assertion and reason: averagesRead the answer and worked solution →Two are true, one is notRead the answer and worked solution →Complete the caution about averagesRead the answer and worked solution →Spot the odd one outRead the answer and worked solution →The mean of a set of observations is found by:Read the answer and worked solution →The three measures of central tendency are:Read the answer and worked solution →
Worked practice questions
What is the average of the first five natural numbers?
- $2$
- $2.5$
- $3$
- $3.5$
Show answer and solution
Correct answer: C. $3$
Sum $= 1+2+3+4+5 = 15$.
Average $= \dfrac{15}{5} = 3$.
A man covers half of a journey at $40$ km/hr and the other half at $60$ km/hr. Find his average speed for the whole journey.
- $45$ km/hr
- $48$ km/hr
- $50$ km/hr
- $52$ km/hr
Show answer and solution
Correct answer: B. $48$ km/hr
For equal distances, average speed is the harmonic mean: $\dfrac{2xy}{x+y} = \dfrac{2 \times 40 \times 60}{100} = \dfrac{4800}{100} = 48$ km/hr.
Option C ($50$, the arithmetic mean) applies only when *time* is split equally, not distance.
How to practise
- Choose a Averages question and try to work out your answer.
- Open the question to check the correct answer and read its worked solution.
- Continue in the app for bite-sized lessons, explanations and review with Quill. You can start without creating an account.