3 workers finish painting a room in 4 hours.
How many hours will it take 4 workers to paint the same room?
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3 workers finish painting a room in 4 hours.
How many hours will it take 4 workers to paint the same room?
To solve this problem, we'll follow these steps:
Let's go through each step in detail:
Step 1: Calculate the work rate for the 3 workers.
If 3 workers can complete the task in 4 hours, then their combined work rate is:
Therefore, the rate of 1 worker is:
Step 2: Determine the equivalent rate when 4 workers are involved.
If each worker has a rate of , then 4 workers would have a combined rate of:
Step 3: Calculate the time required for 4 workers using the combined rate.
To complete 1 room, the time required by 4 workers is:
Therefore, the solution to the problem is 3 hours.
3 hours
What is the ratio between the orange and gray parts in the drawing?
That would give each worker only 1 hour to paint the entire room! Remember, we need to find the rate per worker first, then see how long it takes when workers combine their efforts.
Look for the pattern: more workers = less time for the same job. When one quantity increases and another decreases for a constant amount of work, it's inverse proportion.
That's normal! Work rate problems often give decimal answers. Just make sure to calculate the individual worker rate carefully using fractions: .
Yes! Use: Workers₁ × Time₁ = Workers₂ × Time₂. So 3 × 4 = 4 × Time₂, giving Time₂ = 3 hours. This works because total worker-hours stays constant.
Worker-hours is the total amount of work needed. Think of it as: if 1 worker needs 12 hours, that's 12 worker-hours. Whether it's 3 workers for 4 hours or 4 workers for 3 hours, it's still 12 worker-hours total!
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