Suppose there are X children at the childcare.
Thus :
boys + girls = X
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40% of the children are boys .
Thus :
There are 40/100 × X boys .
So : boys = 0.4X (( Ω ))
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There are 18 more girls than boys
Thus :
girls - boys = 18
girls - ( 40/100 X ) = 18
girls - 0.4X = 18
Add sides 0.4X
girls - 0.4X + 0.4X = 18 + 0.4X
girls = 18 + 0.4X (( μ ))
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Now It's time to put (( μ ))
and (( Ω )) in the above equation.
boys + girls = X
0.4X + 18 + 0.4X = X
0.8X + 18 = X
Subtract sides 0.8X
- 0.8X + 0.8X + 18 = 1X - 0.8X
18 = 0.2X
0.2X = 18
Divided sides by 0.2 (( 2/10 ))
2/10 ÷ 2/10 × X = 18 ÷ 2/10
X = 18 × 10/2
X = 18 × 5
X = 90
Thus there are 90 children at the childcare.
Done.....♥️♥️♥️♥️♥️