Watermelon A is 2 kg lighter than watermelon B and it weighs one fifth of the weight of watermelon C. Watermelons A and C together are 3 times as heavy as watermelon B. How heavy is each watermelon?

Step-by-step explanation:

We can write some equations to describe the given relationships:

  A = B - 2 . . . . . A is 2 kg lighter than B

  A = C/5 . . . . . . A is 1/5 the weight of C

  A+C = 3B . . . . together, A and C are 3 times the weight of B

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Let's solve for A.

  B = A+2 . . . from the first equation

  C = 5A . . . . from the second equation

  A +5A = 3(A+2) . . . . substituting for B and C in the third equation

  6A = 3A +6

  3A = 6

  A = 2

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  B = A+2 = 4

  C = 5A = 10

Watermelon A weighs 2 kg; B weighs 4 kg; and C weighs 10 kg.