Jenson, Zeph, Bryan and David participated in a Science quiz. The average number of points scored by Jenson and Zeph was 78. The average number of points scored by Zeph and David was 70.8. The average number of points scored by Jenson, Zeph and David was 71. The average number of points scored by Bryan and David was 69. How many points did each of them score?

1. David
2. Jenson
3. Zeph
4. Bryan

(a)
Total score of Jenson and Zeph
= 78 x 2
= 156

Total score of Zeph and David
= 70.8 x 2
= 141.6

Total score of Jenson, Zeph and David
= 71 x 3
= 213

David's score
= 213 - 156
= 57

(b)
Jenson's score
= 213 - 141.6
= 71.4

(c)
Zeph's score
= 141.6 - 57
= 84.6

(d)
Total score of Bryan and David
= 69 x 2
= 138

Bryan's score
= 138 - 57
= 81

Answer(s): (a) 57; (b) 71.4; (c) 84.6; (d) 81