Easy does it! The Smart Scholar Method

5 a     + 12 m          + 19 p           = 275 …       …       …       (A)

Look at the equation closely. The number of apples is 7 less than the number of mangoes which is 7 less than the number of pears.

(B) can be  rewritten as:

23 a    + 19 m          + 15 p           = 360  …       …       …       (C)

Look at the equation closely. The number of apples 4 more than the number of mangoes which is 4 more than the number of pears.

(A) x 4 gives   20 a +   48 m    +   76 p = 1100 …     …       (D)

(C) x 7 gives 161 a + 133 m    + 105 p = 2520 …     …       (E)

Adding (D) and (E):

                    181 a + 181 m    + 181 p = 3620

Dividing by 181, a + m + p = 20.

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