First three sum 1/10 + 2/10 + 4/10 Proof: When the numbers in the denominator have the same value, fractions can be compute only with the sum of numerator values and the denominator doesn’t change. 1/10 + 2/10 + 4/10 = 1+2+4 / 10 = 7/10 Second three sum 1/10+1/5 + 2/5, Proof: such kind of fractions can be computed as follows: 1/10 + (1+2 )/5 (same denominators). 1/10 + (1+2 )/5= 1/10 + 3/5= 5x1 +10x3 / 5x10 = 5+30 /50 =35/50, by simplifying by 5, 35/50=7/10 The third three sum is 5/10+ 3/15+8/20,it can be computed by using the same method as given above
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