Question 881143
x = number of girls
2x + 20 = number of boys  {number of boys was 20 more than twice the number of girls}


x + 2x + 20 = 140 {total number of boys and girls was 140}
3x + 20 = 140 {combined like terms}
3x = 120 {subtracted 20 from each side}
x = 40 {divided each side by 3}


there were 40 girls
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