R K Bansal Solutions for Chapter: Percent and Percentage, Exercise 3: EXERCISE 8(C)

If $x$ is $30\%$ more than $y$ find $\frac{y+x}{x}$.

If $x$ is $30\%$ more than $y$ find $\frac{y}{y-x}$.

The weight of a machine is $40 kg$. By mistake, it was weighed as $40.8 kg$. Find the error percent.

From a cask, containing $450$ litres of petrol, $8\%$ of the petrol was leakage and evaporation. How many litres of petrol were left in the cask?

An alloy consists of $13$ parts of copper, $7$ parts of zinc and $5$ parts of nickel. What is the percentage of each metal in the alloy ?

In an examination, first division marks are $60\%$. A student secures $538$ marks and misses the first division by $2$ marks. Find the total marks of the examination.

Out of $1200$ pupils in a school, $900$ are boys and the rest are girls. If $20\%$ of the boys and $30\%$ of the girls wear spectacles, find how many pupils in all wear spectacles.

Out of $1200$ pupils in a school, $900$ are boys and the rest are girls. If $20\%$ of the boys and $30\%$ of the girls wear spectacles. What percent of total pupils wear spectacles?