Question 1130546

Let x = number of sites in Asia

Asia sites + European sites + North American sites = 21
x + (x+4) + ((x+4)+x)+5 = 21
4x + 13 = 21
4x = 8
x = 2  --> x+4 = 6,  x+4+x+5 = 2x+9 = 13

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Ans:  2 sites in Asia, 6 in Europe, 13 in N. America
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