Estimation Using Percentages in Situations

Q.

What percentage of numbers from $1$ to $70$ have $1$ or $9$ in the units digit?

Q. Question 8
Out of 15, 000 voters in a constituency , $60\%$ voted. Find the percentage of voters who did not vote. Can you now find how many actually did not vote?

Q. Question 2 (a)
Convert the following ratios to percentages:
3:4

Q.

How do you write $\frac{1}{8}$ as a percent?

Q.

Vivek gets $60$ marks and fails by $20$ marks in an English Paper where the maximum marks are $200$. Find the pass percentage.

Q.

If $16\%$ of a number is $72$, find the number.

Q.

How do you write $\frac{19}{25}$ as a percent?

Q.

Question 2

Income of Gayatri = Rs. 160000 per year. She pays 15 % of this as house rent and 10 % of the remainder on her child's education. The money left with her is
(a) Rs. 136000
(b) Rs. 120000
(c) Rs. 122400
(d) Rs. 14000

Q.

In an examination, a student has to secure $45\%$ marks to pass the exam. If Varun got $251$ marks and failed by $19$ marks, what are the maximum marks?

Q.

In a class of 35 students 7 students were absent. What is the percentage of students that were present?

1. 80%

2. 20%

3. 30%

4. 70%

Q.

A reaction has a half-life of $1$ min. The time required for $99.9\%$ completion of the reaction is _____ min. (Round off to the nearest integer) [ Use $\ln 2=0.69$, $\ln 10=2.3$]

Q.

A towns population of children increased from $376$ to $421$ during the past year.

Find the equation shows how to find the percent increase?

Q.

A water tank contains $753L750ml$ of water if $189l250ml$of water leak out. Find the remaining amount of water in the tank.

Q.

What percent is:

$12$ of $80$

Q.

$CP$ of an item is $Rs450$. If it is sold at a loss of $10\%$, then its $SP$ $=$$.............$ $[Rs500/Rs405]$

Q.

What is the value of $1\%\mathrm{of}1\%\mathrm{of}25\%\mathrm{of}1000$?

Q.

A water tank can hold$200$liters of water. There is a hole in the tank for which water in the water tank flows out at the rate of $5$ liters per hour. How much water will be left after $7$ hours $?$

Q.

Find $60\%$ of $1litres$ in $mL$.

Q.

Question 9
Meet saves Rs 4000 from her salary. If this is $10\%$ of her salary. What is her salary and also find her net spending? However, Meet wanted to buy a bike, so she started to save $30\%$ of her salary. How much is she saving now?

Q.

Find the value of:

$60\%\text{of}50kg$

Q.

Find the value of each of the following:

$125\%$ of $4$ hours $40$ minutes.

Q.

Find the value of:

$16\%\text{of}175$

Q.

What is the complement of $\frac{1}{3}of90°$

Q. A student has to secure $35\%$ marks to pass. He got $80$ marks and failed by $60$ marks. Find the maximum marks.

1. $100$
2. $200$
3. $300$
4. $400$

Q.

There are $160$eggs in a tray. $15\%$ of the eggs broke. How many good eggs are there in the tray?

Q.

John bought a sofa set for Rs $4500$ and sold it for Rs $4200$. Find his loss per cent.

Q.

$13$ of the $18$ players on the varsity soccer team are seniors. What percent of the players on the team are not seniors?

Q. If a car increases its speed from 100 km/hr to 110 km/hr in one second, find the increase in speed in percentage.

1. 5%
2. 10%
3. 15%
4. 20%

Q.

Relative error =

1. $\frac{ActualValue}{AbsoluteError}$

2. $\frac{AbsoluteError}{ActualValue}$

3. $\frac{PercentageError}{ActualValue}$

4. $\frac{ActualValue}{PercentageError}$

Q.

Express each of the following as a percent

$\frac{2}{25}$