Question

There are 250 people in a museum.
2/5 of the 250 people are girls.
3/10 of the 250 people are boys.
The rest of the people are adults.
Work out the number of adults in the museum.

Answer 1

Given,

Total number of people = 250

Fraction of people who are girls = 2/5 =

$\frac{2}{5} \times 250 = 2 \times 50 = 100$

Fraction of people who are boys = 3/10=

$\frac{3}{10} \times 250 = 3 \times 25 = 75$

Let the number of adults be x.

Now, According to question,

Number of girls + number of boys + number of adults = 250

Now, putting the values we have,

100 + 75 + x = 250

=> 175 + x = 250

=>x = 250 - 175

=> x = 175.

Therefore total number of adults is 175

Hope the answer helps you.