There are two leaders in the tourist group, with an average age of 30 years and several children with an average age of 10 years. The total age of the group is 12 years. How many children are in the group?

Correct result:

d =  18


12 •(2+d) = 30•2+10•d

2d = 36

d = 18

Our simple equation calculator calculates it.

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