Data Sufficiency

The total cost of producing item X is equal to the sum of item X's fixed cost and variable cost. If the variable cost of producing X decreased by 5% in January, by what percent did the total cost of producing item X change in January?

(1) The fixed cost of producing item X increased by 13% in January.

(2) Before the changes in January, the fixed cost of producing item X was 5 times the variable cost of producing item X.

OA: C

piyush_nitt wrote:The total cost of producing item X is equal to the sum of item X's fixed cost and variable cost. If the variable cost of producing X decreased by 5% in January, by what percent did the total cost of producing item X change in January?

(1) The fixed cost of producing item X increased by 13% in January.

(2) Before the changes in January, the fixed cost of producing item X was 5 times the variable cost of producing item X.

OA: C

tc0: before jan. total cost
vc0: before jan. variable cost
fc0: before jan. fixed cost

tc0 = vc0 + fc0

tc: new total cost
vc: new variable cost
fc: new fixed cost

vc = 0.95 * vc0

(1) fc = 1.13 * fc0

tc = vc + fc = [0.95 * vc0] + [1.13 * fc0]

tc0 = vc0 + fc0

2 equations, 3 variables

Insuff

(2) fc0 = 5 * vc0

tc0 = vc0 + [5 * vc0]

tc = vc + fc

2 equations, 3 variables

Insuff

(1) & (2)- 3 equations, 3 variables. Solvable.

Suff [spoiler][C][/spoiler]