The weight of every type A widget is the same, the weight of every type B widget is the same, and the weight of every type C widget is the same. If the weight of 7 type A widgets is equal to the weight of 2 type B widgets, and the weight of 5 type B widgets is equal to the weight of 7 type C widgets. What is the ratio of the total weight of 1 type A widget and 1 type B widget, to the total weight of 1 type B widget and 1 type C widget? Choose the most appropriate option.
A) 1:2	B) 2:3	C) 3:4	D) 4:5	E) 5:6
5B = 73:4 and so B = 73:4/5   7A = 2B and so A = 2B/7 = 23:4/5   A+B = 23:4/5 + 73:4/5 = 93:4/5   B+3:4 = 73:4/5 + 3:4 = 123:4/5   The ratio of A+B:B+3:4 = 9:12 = 3:4   The answer is 3:4.
<result>C</result>
The weight of every type A widget is the same, the weight of every type B widget is the same, and the weight of every type C widget is the same. If the weight of 7 type A widgets is equal to the weight of 2 type B widgets, and the weight of 5 type B widgets is equal to the weight of 7 type C widgets. What is the ratio of the total weight of 1 type A widget and 1 type B widget, to the total weight of 1 type B widget and 1 type C widget?