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Question
The ratio of boys and girls in a school is 12 : 5. If the number of girls is 840, the total strength of the school is
Options
1190
2380
2856
2142
Solution
2856
Ratio of boys and girls = 12:5
Let x be any number such that the number of boys and girls are 12x and 5x, respectively.
Number of girls = 840
5x = 840
⇒ x = `840/5` = 168
Number of boys = 12x= 12 × 168 = 2016
Number of girls = 840
Total strength of the school = 2016 + 840 = 2856
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