NCERT Solutions for Chapter: Direct and Inverse Proportions, Exercise 1: Exercise

If two quantities $p$ and $q$ vary inversely with each other, then

It is given that $l$ varies directly as $m$. Write an equation which relates $l$ and $m$.

It is given that $l$ varies directly as $m$. Find the constant of proportion $( k )$, when $l$ is $6$ then $m$ is $18$ .

Find the values of $x$ and $y$, if $a$ and $b$ are in inverse proportion.

If $25 \mathrm{metres}$ of cloth costs $₹337.50$, then

What will be the cost of $40 \mathrm{metres}$of the same type of cloth?

The variable $x$ is inversely proportional to $y$. If x increases by $p\%$, then by what per cent will $y$ decrease?

The following table shows the distance travelled by one of the new eco-friendly energy-efficient cars travelled on gas.

Which type of properties are indicated by the table? How much distance will be covered by the car in $8 \mathrm{litres}$ of gas?

Kritika is following this recipe for bread. She realises her sister used most of sugar syrup for her breakfast. Kritika has only $\frac{1}{6}$ cup of syrup, so she decides to make a small size of bread. How much of each ingredient shall she use?

Bread recipe

$1$ cup quick cooking oats

$2$ cups bread flour 

$\frac{1}{3}$ cup sugar syrup

$1$ tablespoon cooking oil

$1\frac{1}{3}$ cups water

$3$ tablespoons yeast

$1$ teaspoon salt.