Question

A dwarf decides to visit three of her friends. She carries 7 apples in a sack. To reach her 1st friend she has to cross a magic river. After crossing the river, the number of apples in her sack doubles. She then gives her 1st friend a number of apples. She continues her journey and then crosses the 2nd magic river. The number of apples doubles again. She gives her 2nd friend the same number of apples. She crosses the 3rd magic river. Again the number of apples doubles. She visits her 3rd friend and gives the same number. again. This time there are NO apples left.

•What number did she give to each friend?
• Investigate with different start numbers. • What numbers work out neatly?​

Answer 1

She gave 8 apples to each friend.

Explanation:

2{[2(14-x)]-x} = 0 Distribute the 2

2[28-2x -x) -x = 0 Combine like terms

2(28 -3x) -x = 0 Distribute the 2

56 - 6x - x= 0 Combine like terms

56 -7x = 0 Subtract 56 from both sides

-7x = -56 Divide both sides by -7

x = 8

Check:

7 x 2 = 14

14 - 8 = 6

6 x 2 = 12

12 - 8 = 4

4 x 2 = 8

8 - 8 = 0

Checks.

Helping in the name of Jesus