Final answer:
To find the length of a chain made from 40 links, subtract the length of a chain with two links from a chain with three links to find the difference. Then, divide the difference by 1 to find the length of a single link. Finally, multiply the length of a single link by 40 to find the length of the chain made from 40 links.
Step-by-step explanation:
To find the length of a chain made from 40 links, we need to determine the length of a single link. We can do this by finding the difference in length between the chain with two links and the chain with three links.
First, we find the difference in length between the chain with three links and the chain with two links: 18 cm - 13 cm = 5 cm.
Next, we find the length of a single link by dividing the difference in length by 1: 5 cm ÷ 1 = 5 cm.
Finally, we find the length of the chain made from 40 links by multiplying the length of a single link by 40: 5 cm × 40 = 200 cm.