Question

$\frac{3.86}{x}+\frac{180.2}{10x}+\frac{42.2}{5x}$
The following equation represents the format of the Ironman: it consists of a $3.86$-km swim, an $180.2$-km bicycle ride, and a $42.2$-km run, all raced in that order and without a break. Suppose M.S. Hussain bikes $10$ times as fast as he swims and runs $5$ times as fast as he swims. Here, $x$ represents the rate at which the Hussain swims, and the whole expression represents the number of hours that it takes him to complete the race. If it takes him $16.2$ hours to complete the race, Calculate the distance swam kilometres by him in $1$ hour.

• A. 0.85
• B. 1.01
• C. 1.17
• D. 1.87

Answer 1

Answer: (D)

1.87

Since $x$ represents the rate at which Hussain swims, meaning that it shows the speed of his swimming, i.e. the distance swam by him in $1$ hour.

Thus, we need to find $x$ as asked in the question.

$\frac{3.86}{x}+\frac{180.2}{10x}+\frac{42.2}{5x}=16.2$

$\therefore \frac{38.6+180.2+84.4}{10x}=16.2$

$\therefore 303.2=162x$

$\therefore x=1.87$ km/hour