Question

If the interest on Rs. $200$ be Rs. $25$ in a certain time, what will be the interest on Rs. $750$ for the same time?

Answer 1

Hint: Read the question twice and understand the type of question, mainly here it suggests the set of proportion. Proportion throughout remains the same, if we increase the amount the interest also increases since it is directly proportional to each other. Frame the equation with the given relation to get the unknown interest occurred with the increased amount by using the application of ratio and proportion.

Complete step by step answer:
Given that: Interest on Rs. $200 = 25$Rs.
Therefore, interest on Rs. $1 = \dfrac{{25}}{{200}}$
So, the interest on Rs. $750 = \dfrac{{25}}{{200}} \times 750$
Simplify the above expression finding the factors of the terms.
$ = \dfrac{{25 \times 750}}{{25 \times 8}}$
Common factors from the numerator and the denominator cancel each other and therefore remove from the numerator and the denominator.
$ = \dfrac{{750}}{8}$
Simplify the above expression finding the division of the terms.
$ = 93.75$Rs.

Additional Information: Ratio can be defined as the comparison between two numbers without any units.
Whereas, when two ratios are set equal to each other are known as the proportion.
Four numbers a, b, c, and d are said to be in the proportion. If $a:b = c:d$whereas, four numbers are called to be in continued proportion if the terms are expressed as $a:b = b:c = c:d$

Note: Always read the question twice and frame the word statement in the correct mathematical form by checking it twice. Segregate all the known and unknown terms and form the corresponding ratios and the proportions accordingly identifying the direct proportion or inverse proportion.