The average number of questions Lee and Irene solved was 209. The average number of questions Irene and Zara solved was 196. The average number of questions Zara and Lee solved was 178. How many questions did each of them solve?
- Irene
- Lee
- Zara
(a)
Number of questions that Lee and Irene solved
= 209 x 2
= 418
Number of questions that Irene and Zara solved
= 196 x 2
= 392
Number of questions that Zara and Lee solved
= 178 x 2
= 356
Number of questions that Irene solved
= (418 + 392 - 356) ÷ 2
= 454 ÷ 2
= 227
(b)
Number of questions that Lee solved
= 418 - 227
= 191
(c)
Number of questions that Zara solved
= 392 - 227
= 165
Answer(s): (a) 227; (b) 191; (c) 165
