If 7 spiders make 7 webs in 7 days, then one spider will make one web in how many days?

Given data

• 7 spiders → 7 webs in 7 days.

Concept / Approach

• Work is proportional to spider-days. Compute rate per spider-day.

Step-by-step calculation

Total spider-days = 7 spiders × 7 days = 49 spider-daysWebs made = 7 ⇒ rate = 7 / 49 = 1/7 web per spider-dayFor 1 spider to make 1 web: days = 1 ÷ (1/7) = 7 days

Verification

1 spider in 7 days produces 1 web at 1/7 per day; scales consistently.

Common pitfalls

• Assuming 1 day by symmetry; must consider rate via spider-days.

Final Answer

7 days