Let x be the number of 2 mark questions, y be the number of 5 mark questions.
1) x + y = 17 or x = 17 - y
2) 2x + 5y = 70
substitute eq(1) into eq(2):
2(17 - y) + 5y = 70
34 - 2y + 5y = 70
3y = 36
y = 12
using eq(1):
x = 17 - 12 = 5
check using eq(2):
2(5) + 5(12) = 70
10 + 60 = 70
70 = 70
Rajinder correctly answered 5 two point questions and 12 five point questions.