Question

Question 33

State whether the given statements are true (T) or false (F).

If b : a = c : d, then a, b, c and d are in the proportion

Answer 1

Four quantities are said to be in proportion if the ratio of the first and the second quantities is equal to the ratio of the third and the
fourth quantities. The symbol ‘::’ or ‘=’ is used to equate the two ratios. The order of terms in a proportion is important. For example 3, 8, 24, 64 are in proportion but 3, 8, 64, 24 are not in proportion.

Now, if $b:a=c:d\Rightarrow \frac{b}{a}=\frac{c}{d}\Rightarrow ac=bd$
If a, b, c and d are in proportion, then a : b = c:d
$\Rightarrow \frac{a}{b}=\frac{c}{d}\Rightarrow ad=bc$

Hence, the given statement is false.