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1. How long will it take 4 machines to produce 100 items?

2. How many items do 8 machines produce in 45 minutes?

3. If a rescue vessel has enough provisions for 10 people to survive for 6 days, how long will 12 people survive on the vessel?

4. A motorist takes 4.5 hours to reach his destination at [tex]$80 \text{ km/h}$[/tex].

a. If he wants to complete his journey in 4 hours, at what speed must he travel?

b. If he drives at [tex]$110 \text{ km/h}$[/tex], how long will the journey be? Give the answer in hours.

Answer :

Certainly! Let's go through each question step-by-step.

### 1. How long will it take 4 machines to produce 100 items?

To find out how long it takes, we use the concept of rate. If we assume each machine produces 1 item per minute:

- Rate of 1 machine: 1 item per minute.
- Rate of 4 machines: 4 items per minute (since 4 machines each produce 1 item per minute).

We want to produce 100 items, so:

- Total time needed = Total items ÷ Rate of production = 100 items ÷ 4 items per minute = 25 minutes.

### 2. How many items do 8 machines produce in 45 minutes?

With 8 machines, each assumed to produce 1 item per minute:

- Rate of 8 machines: 8 items per minute.

In 45 minutes, the total production is:

- Items produced = Rate × Time = 8 items/minute × 45 minutes = 360 items.

### 3. If a rescue vessel has enough provisions for 10 people to survive for 6 days, how long will 12 people survive on the vessel?

This problem involves proportional reasoning:

- Total provisions measured in person-days = 10 people × 6 days = 60 person-days.

If there are 12 people on the vessel, the number of days they can survive is:

- Survival days = Total provisions ÷ Number of people = 60 person-days ÷ 12 people = 5 days.

### 4. A motorist takes 4.5 hours to reach his destination at 80 km/h. If he wants to complete his journey in 4 hours, at what speed must he travel?

Calculate the total distance first:

- Distance = Speed × Time = 80 km/h × 4.5 hours = 360 km.

If he wants to cover the same distance in 4 hours:

- Required speed = Distance ÷ Desired time = 360 km ÷ 4 hours = 90 km/h.

### 5. If he drives at 110 km/h, how long will the journey be?

Using the previously calculated distance of 360 km:

- Time = Distance ÷ Speed = 360 km ÷ 110 km/h ≈ 3.27 hours (approximately 3 hours and 16 minutes).

These are the detailed solutions for each question based on the information given.