CAT 2001 — QA Question 25
3 Variable EquationsEasy
At a certain fast food restaurant, Brian can buy 3 burgers, 7 shakes, and one order of fries for Rs. 120 exactly. At the same place it would cost Rs. 164.5 for 4 burgers, 10 shakes, and one order of fries. How much would it cost for an ordinary meal of one burger, one shake, and one order of fries?
Answer & solution
Rs. 31
- B
Rs. 41
- C
Rs. 21
- D
Cannot be determined
Solution
Let the cost of one burger, one shake and one order of fries be b, s and f respectively.
∴ 3b + 7s +1f = 120 ...(i)
∴ 4b + 10s + 1f = 164.5 ...(ii)
Subtracting (i) from (ii), we get,
1b + 3s = 44.5
Multiplying by 2, we get,
2b + 6s = 89 ...(iii)
Subtracting equation (iii) from equation (i), we get,
b + s + f = 31
Hence, option (a).