Question

• always use significant figure rules. remember that these rules apply to all numbers that are measurements.

you travel 20.0 mph for 0.500 hour, 40.0 mph for 1.00 hour, 30.0 mph for 0.500 hour, and 50.0 mph for 2.00 hours.
what is the total distance traveled?
○ 165 miles
○ 170 miles
○ 160 miles
○ 200 miles

Explanation:

Step1: Calculate distance for first segment

Distance formula: \( d = v \times t \)
\( v = 20.0 \) mph, \( t = 0.500 \) h
\( d_1 = 20.0 \times 0.500 = 10.0 \) miles

Step2: Calculate distance for second segment

\( v = 40.0 \) mph, \( t = 1.00 \) h
\( d_2 = 40.0 \times 1.00 = 40.0 \) miles

Step3: Calculate distance for third segment

\( v = 30.0 \) mph, \( t = 0.500 \) h
\( d_3 = 30.0 \times 0.500 = 15.0 \) miles

Step4: Calculate distance for fourth segment

\( v = 50.0 \) mph, \( t = 2.00 \) h
\( d_4 = 50.0 \times 2.00 = 100.0 \) miles

Step5: Sum all distances

\( d_{total} = d_1 + d_2 + d_3 + d_4 \)
\( d_{total} = 10.0 + 40.0 + 15.0 + 100.0 = 165.0 \) miles (considering significant figures, it rounds to 165 miles as the least number of decimal places in the additions is 0, and the sum is 165 which has three significant figures consistent with the measurements)

Answer:

165 miles