There are 72 pupils taking part in an international mathematic competition. 4 9 of the pupils are girls. How many boys are there?
To find out how many boys there are, we first need to figure out how many girls there are since we are given that \( \frac{4}{9} \) of the pupils are girls.
There are 72 pupils in total and \( \frac{4}{9} \) of these pupils are girls. To find out the number of girls, we can multiply the total number of pupils by \( \frac{4}{9} \):
Number of girls = \( 72 \times \frac{4}{9} \)
Now let's do the calculation:
Number of girls = \( 8 \times 4 \) (since \( 72 ÷ 9 = 8 \))
Number of girls = 32
Now that we know how many girls there are, we can subtract this number from the total number of pupils to find out how many boys there are:
Number of boys = Total number of pupils - Number of girls
Number of boys = 72 - 32
Number of boys = 40
So, there are 40 boys in the international mathematic competition.