average age of 7 boys is 20 years. If average age of the first six boys is 19.5 years then the 7th boy will be how many year old?​

1 thought on “average age of 7 boys is 20 years. If average age of the first six boys is 19.5 years then the 7th boy will be how many year old?​”

1. The seventh boy will be :

   20 × 7 – 6 × 19.5

   => 140 – 117.0 = 23 Years ✔✔

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