The average number of questions Dylan and Zoe solved was 213. The average number of questions Zoe and Erika solved was 190. The average number of questions Erika and Dylan solved was 178. How many questions did each of them solve?
- Zoe
- Dylan
- Erika
(a)
Number of questions that Dylan and Zoe solved
= 213 x 2
= 426
Number of questions that Zoe and Erika solved
= 190 x 2
= 380
Number of questions that Erika and Dylan solved
= 178 x 2
= 356
Number of questions that Zoe solved
= (426 + 380 - 356) ÷ 2
= 450 ÷ 2
= 225
(b)
Number of questions that Dylan solved
= 426 - 225
= 201
(c)
Number of questions that Erika solved
= 380 - 225
= 155
Answer(s): (a) 225; (b) 201; (c) 155
