C IMO.

1) No cost mentioned - Insufficient
2) We could have diff ratios to produce $8

Together, 2(4) + x(10) + 1(6)/3+x = 8

x = 5. So ratio would be 2:5:1.

winny wrote:In what proportions should coffee of type A, type B and type C be mixed to get coffee which costs $8 for every 100 ounces?

1) The ratio in which coffee of type A and type C are mixed is 2:1.

2) Coffee of type A, type B and type C cost $4, $10 and $6 respectively for 100 ounces.

Don't have the OA.

I would also say [spoiler](C)[/spoiler]

This is an average (arithmetic mean) question. We have three types of coffee A, B, and C, mixed together they should cost $8 (the average) per 100g.

8 * 3 = 24

Combining both statements together, you can add the costs of the coffee types to find the sum 24 (8 * 3 = 24).

Double the cost of coffee type A, because the ratio in which coffee of type A and type C are mixed is 2:1.

2(4) + 6 (coffee type C) = 14

24 - 14 = 10, hey that's the cost coffee type B!!! 8 + 6 + 10 = 24

$24 / 3 = $8