Answer:
20 1 Liter Cartons
40 700 ml Cartons
Explanation:
Let A be the number of 700ml cartons.
Let B be the number of 1 L cartons
We are told that A + B = 60 cartons total
Rearrange to isolate A: A = 60 - B
700ml is 0.700L
Total volume of milk is 48L
Total volume (in liters) of the 700 ml cartons is from (0.70 L)A
Total volume from the 1L cartons is (1 L)B
Total = (0.70)A + 1B = 48 L
Now use the rearranged equation for A in the above espression:
(0.70)A + 1B = 48 L
(0.70)(60-B) + 1B = 48 L
42 - 0.70B + B = 48
0.30B = 6
B = 20
A is 60 - B or 40
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CHECK:
B: 20*(1 L) = 20 L
A: 40*(0.70 L) = 28 L
Total = 48 L YES