Question

a. A chemist needs 200ml of a 1.5% acidic solution. Two other acidic solutions - 0.8% and 3.2% - are available for mixing. How much of each solution should be mixed to produce the desired solution?

b. A hotel has 260 rooms. Some are singles, and some are doubles. The singles cost $35 and the doubles cost $60. Because of a math teachers' convention, all of the hotel rooms are occupied. The sales for this night are $14,000. How many of each type of room does the hotel have?

Answer 1

what is it?

Answer 2

(a) 0.8x + 3.2(200-x) = 1.5(200)

(b)
s+d = 260
35s+60d = 14000

now just solve the equations.

Answer 3

volume of the 0.8% solution -- x ml
volume of the 3.2% solution = 200-x ml

.08x + .032(200-x) = .015(200)
times 1000
80x + 32(200-x) = 15(200)
solve for x

b) number of single rooms --- x
number of double rooms = 260-x
35x + 60(260-x) = 14000
solve for x

$35 for a motel room??
Time to update those textbooks