Answer:

58%

Step-by-step explanation:

let the boys of the class be 'x'.

therefore,

42+x=100

x=100-42

=58%

Ans:There are 58% boys in the class.

We know that it's 100%

it means "by 100"

we are already given 42% it means 42 per cent.. cent means 100

there for easily by subtracting 42 from 100, we get 58.

It means 58%.!

hope it helps...!

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