Tag: finding percentage of a number

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Questions Related to finding percentage of a number

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

Two-third of one-seventh of a number is $87.5$% of $240$. What is the number?

  1. $2670$
  2. $2450$
  3. $2205$
  4. $1470$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Given, $\dfrac {2}{3}$ of $\dfrac {1}{7}$ of a number say $x$ is $87.5\%$ of $240$.

$\therefore \displaystyle \frac{2}{3}\times\frac{1}{7}\times x=\frac{87.5}{100}\times240$

$\displaystyle \Rightarrow x =\frac{87.5\times240\times3\times7}{2\times100}=2205$
therefore, the number is $2205$.

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

John estimated that the repairs to his car would cost $200$ rupees. In fact they cost $350$ rupees. What was the percentage error?

  1. $52.85\%$
  2. $42.85\%$
  3. $32.85\%$
  4. $22.85\%$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Given that: Expected repair of car= $200$
Actual cost of repair = $ 350$
Percentage of error: $\dfrac{Absolute \ value - exact \ value}{Exact \ value} \times 100$
$= \dfrac{350 - 200}{350} \times{100}$

$= 42.85 $ %

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

You expected to get $50$ gifts for your birthday, but you only got $32$. What was the percentage error?

  1. $51.25\%$
  2. $45.25\%$
  3. $46.25\%$
  4. $56.25\%$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Given, absolute value $=50$, exact value $=32$
Percentage error $=$ $\left | \dfrac{Absolute \space\ value - exact \space\ value}{exact\space\ value} \right |\times 100$ $\%$
$=$ $\left | \dfrac{50 - 32}{32} \right |\times 100$ $\%$
$=$ $\left | \dfrac{ 18}{32} \right |\times 100$ $\%$
$=$ $\left | 0.5625\right |\times 100$ $\%$
$= 56.25\%$

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

Choose the correct answer from the alternatives given.
Some money was lent on $4\%$ compound interest. If the difference in interest of second and the first year is $88$, find out the sum.

  1. $Rs. 50,000$
  2. $Rs. 60,000$
  3. $Rs. 65,000$
  4. $Rs. 55,000$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

For compound interest at rate r, the interest in the first year is P*r and in the second year is P*r*(1+r). The difference is P*r^2. Given r=0.04 and difference=88, we have P*(0.04)^2 = 88, so P*0.0016 = 88, which gives P = 55,000.

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

Choose the correct answer from the alternatives given.
Directions for question 71 to 75: Study the following table carefully and answer the questions given below.
Number of Students Enrolled
With Five Colleges over the Years

Year/College A B C D E
2004 450 320 400 480 520
2005 480 350 380 500 540
2006 420 300 410 520 460
2007 460 360 430 470 480
2008 470 340 390 530 530

What is the average number of students enrolled in the college A over the years? 

  1. $456$
  2. $460$
  3. $464$
  4. $452$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Total number of students in college over the years$=420+480+420+460+470=2280$

Average no. of students$=2280/5=456$

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

$60 \% \text { of } 264$ is the same as-

  1. $10 \% \text { of } 44$
  2. $15 \% \text { of } 1056$
  3. $30 \% \text { of } 132$
  4. $17 \% \text { of } 544$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$60\% \ of \ 264 =\dfrac{60}{100} \times 264 =158.4$


Also, $15\% \ of \ 1056 =\dfrac{15}{100} \times 1056 = 158.4$

Hence, $60\% \ of \ 264 = 15\% \ of \ 1056$

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

$0.15 \% \text { of } 33 \frac { 1 } { 3 } \% \text { of } \mathrm { Rs } .10,000$ is?

  1. $\mathrm { Rs } .0 .05$
  2. $\mathrm { Rs } .5$
  3. $\mathrm { Rs } .105$
  4. $\mathrm { Rs } .150$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Given 


$0.15\% \times 33\dfrac 13\% \times 10000$

$\implies \dfrac {15}{100}\times \dfrac 1{100}\times \dfrac {100}3 \times \dfrac 1{100}\times 10000$

$\implies \dfrac {15}3=5$