Question

Show that 30, 40, 45 and 60 are in proportion.​

Answer 1

We know that,

Product of Means = Product of Extremes

40×45 , 30×60

1800 = 1800

LHS = RHS

Hence, Yes, 30, 40, 45 and 60 are in proportion.

Answer 2

Given numbers are,

$30, 40, 45, 60$

We have to prove that the given numbers are in proportion.

Ratio of $30,40$

$\frac{30}{40}$

$\frac{3\times10}{4\times10}$

The number $10$ which is in both the numerator and denominator get cancelled.

We get,

$\frac{3}{4}$

Ratio of $30,40$ is $3:4$

Ratio of $45,60$

$\frac{45}{60}$

$\frac{3\times15}{4\times15}$

The number $15$ which is in both the numerator and denominator get cancelled.

We get,

$\frac{3}{4}$

Ratio of $45,60$ is $3:4$

Therefore, the given numbers are in proportion.