Tina has 11 marbles fewer than Rachel but 21 marbles more than Billy. The three children have 146 marbles altogether.
- How many marbles does Billy have?
- How many marbles does Rachel have?
(a)
Number of marbles Rachel has = 1 u
Number of marbles Tina has = 1 u - 11
Number of marbles Billy has = 1 u - 11 - 21 = 1 u - 32
Total number of marbles
= 1 u + 1 u - 11 + 1 u - 32
= 3 u - 43
3 u - 43 = 146
3 u = 146 + 43
3 u = 189
1 u = 189 ÷ 3 = 63
Number of marbles that Billy has
= 1 u - 32
= 63 - 32
= 31
(b)
Number of marbles that Rachel has
= 1 u
= 63
Answer(s): (a) 31; (b) 63
