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3 years ago

Jonathan’s class has 30 boys. Of the students in his class, 60% are girls. How many girls are in Jonathan’s class?

Mathematics

1 answer:

raketka [301]3 years ago

5 0

Answer:

45 girls

Step-by-step explanation:

Remark
There are only 2 choices for gender. So if the class is 60% girls, the there must be 100 - 60 = 40% for the boys.
But we are told that the boys are 30 in number.
Let x = the total number of students.

Solution

40/100 * x = 30 Change the % to a decimal
0.4 x = 30 Divide both sides by 0.4
0.4 x / 0.4 = 30 / 0.4 Do the division
x = 30/0.4
x = 75 students in total

Formula

Total of Boys and Girls = Number of boys + number of girls.

Givens

Total = 75
Number of boys = 30

Solution II

75 = x + 30 Subtract 30 from each side
75 - 30 = x +30 - 30
45 = x
There are 45 girls in the class.

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