Answer :

Answer:

784 : 896

Step-by-step explanation:

sum the parts of the ratio

7 + 8 = 15 parts

divide the quantity by 15 to find the value of one part of the ratio

1680 ÷ 15 = 112 ← value of 1 part of the ratio, then

7 parts = 7 × 112 = 784

8 parts = 8 × 112 = 896

Thus 1680 in the ratio 7 : 8 = 784 : 896