130kg of an alloy A is mixed with 160 kg of alloy B. If alloy A has lead and tin in the ratio 2:3 and alloy B has tin and copper in the ratio 3:4, then the amount of tin in the new alloy is? Choose one.
A) 140.6 kg
B) 145.3 kg
C) 146.5 kg
D) 110.8 kg
E) 114 kg

Rationale: "quantity of tin in 130 kg of a = 130 * 3 / 5 = 78 kg quantity of tin in 160 kg of b = 160 * 3 / 7 = 68.5 kg quantity of tin in the new alloy = 78 + 68.5 = 146.5 kg answer is c"
Answer: C