the distance from Earth to Mars is 136,000,000 miles. A spacecraft travels at an average speed of 28,500 kilometers per hour. Determine, to the nearest day, how long it will take the spacecraft to reach Mars. [ 1 kilometer=0.6 miles]

Answer

To determine how long it will take a spacecraft traveling at an average speed of 28,500 kilometers per hour to reach Mars, which is 136,000,000 miles away, we can follow these steps:

### Step 1: Convert the speed from kilometers per hour to miles per hour.
Given that 1 kilometer = 0.6 miles, we can convert the speed:

\[ \text{Speed in miles per hour} = 28,500 \text{ km/h} \times 0.6 \text{ miles/km} \]

\[ \text{Speed in miles per hour} = 17,100 \text{ miles per hour} \]

### Step 2: Use the formula for time.
The formula for time is given by:

\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]

### Step 3: Substitute the values into the formula.
The distance to Mars is 136,000,000 miles, and the speed we calculated is 17,100 miles per hour:

\[ \text{Time} = \frac{136,000,000 \text{ miles}}{17,100 \text{ miles/hour}} \]

### Step 4: Calculate the time in hours.
Now we perform the division:

\[ \text{Time} = 7,964.5 \text{ hours} \]

### Step 5: Convert hours to days.
To convert hours to days, we divide by the number of hours in a day (24):

\[ \text{Time in days} = \frac{7,964.5 \text{ hours}}{24 \text{ hours/day}} \approx 332.69 \text{ days} \]

### Step 6: Round to the nearest day.
Rounding 332.69 to the nearest whole number gives us:

\[ \text{Time in days} \approx 333 \text{ days} \]

### Final Answer:
It will take approximately **333 days** for the spacecraft to reach Mars.

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