Question
The average age of 13 girls is 40 years. If the age of
one more girl is added the average decreases by half a year. What is the age of new girl?Solution
Total age of 13 girls = 13 × 40 = 520 years If the age of one more girl is added the average decreases by half a year, ∴ Total age of 14 girls = 39.5 × 14 = 553 Now, Age of the new person = 553 – 520 = 33 years
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