Question

Are the numbers 21, 9, 35, 10 in proportion?​

Answer 1

Step-by-step explanation:

to check if 21:9:35:10 are in proportion

21 × 10 = 210

9 × 35 = 315

as product of extreme ≠ product of mean

goven numbers are not in proportion

Answer 2

★ How to do :-

Here, we are given with four numbers in which we are asked to find out whether the given four numbers can form a proportion or not. In the first method we will be using the basic application of products of means and extremes while in the second method we will converting the ratios in the proportional form into fractions and find out whether the terms are in proportion or not. So, let's solve!!

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➤ Solution :-

Method 1 :-

${\tt \leadsto 21, 9, 35, 10}$

Write the given numbers in proportional series.

${\tt \leadsto 21 : 9 :: 35 : 10}$

Multiply the means and extremes.

Here,

Means :- 9 and 35

Extremes :- 21 and 10

Product of means :- ${\tt 9 \times 35 = 315}$

Product of extremes :- ${\tt 21 \times 10 = 210}$

${\tt \leadsto 315 \neq 210}$

Thus, they cannot form a proportion.

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Method 2 :-

${\tt \leadsto 21, 9, 35, 10}$

Write the given numbers in proportional series.

${\tt \leadsto 21 : 9 :: 35 : 10}$

Write both ratios in fractional form.

${\tt \leadsto \dfrac{21}{9} \: \: and \: \: \dfrac{35}{10}}$

Cross multiply the numbers.

${\tt \leadsto 21 \times 10 \: \: and \: \: 35 \times 9}$

${\tt \leadsto 210 \neq 315}$

Thus, they cannot form a proportion.

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Hence solved !!