How do i solve this problem? please include how you did it and answer?

r + g = 12 --> r = 12 - g

.95r + 1.25g = 12(1.15)

now sub 12 - g in for r in the 2nd equation...

.95r + 1.25g = 12(1.15)

.95(12 - g) + 1.25g = 13.8

11.4 - .95g + 1.25g = 13.8

.30g = 13.8 - 11.4

.30g = 2.4

g = 2.4/.30

g = 8

now sub 8 in for g in either of the original equations...

r + g = 12

r + 8 = 12

r = 12 - 8

r = 4

you will need 4 lbs. of red grapes which equals (4 x .95) = 3.80

you will need 8 lbs of green grapes which equals (8 x 1.25) = 10.00

add together and you get 12 lbs at 13.80. Now divide 13.80 by 12 = 1.15 per pound.

Pounds of red grapes = y

Pounds of green grapes = (12-y)

Cost of red grapes = 0.95 * y

Cost of green grapes = 1.25 * (12-y)

Total cost of grapes = 12 * 1.15 = 13.8

0.95y + 1.25 (12-y) = 13.8

0.95y + 15 - 1.25y = 13.8

15 - 0.3 y = 13.8

- 0.3y = 13.8 - 15

- 0.3 y = -1.2

3y = 12

y = 4

Pounds of red grapes = y = 4

Pound of green grapes = (12-y) = 8

1) r + g = 12 or r = 12 - g

2) 95r + 124g = 115(12)

substitute equation(1) into equation(2):

95(12 - g) + 124g = 1380

1140 - 95g + 124g = 1380

29g = 240

g = 240/29 = 8.3 pounds

using equation(1):

r = 12 - 8.3 = 3.7 pounds

check using equation(2):

95(3.7) + 124(8.3) = 1380

351.5 + 1029.2 = 1380

1380.7 = 1380 due to rounding

Mix 3.7 pounds of red grapes and 8.3 pounds of green grapes.

- .--

r = lb's of red grapes

g = lb's of green grapes

r + g = 12

.95r + 1.25g = 12 x $1.15

.95r + 1.25(12-r)= $13.80

.95r - 1.25r +15 = $13.80

-.30r = -$1.20

r = 4lb

4lb + g= 12

g = 8lb

Check:

4lb x .95 + 8lb x 1.25 = $13.80