Unit ConversionsUnit ConversionsQ - How many kilometers are in 47 miles?

(note: 1 km = 0.621 miles)

First identify the desired quantity.

# km

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

Next write down the starting quantity… the starting point of

calculations.

47 mi

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

Now we have to choose a

conversion factor

47 mi

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

What conversion factors are possible?

47 mi 1 km 0.621 mi

0.621 mi 1 km

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

Pick the one that will allow you to cancel

out miles

47 mi 1 km 0.621 mi

0.621 mi 1 km

Pick the one that will allow you to cancel

out miles

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

47 mi 1 km 0.621 mi

0.621 mi 1 km

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

Cross out common factors

47 mi x 1 km 0.621 mi

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

Now finish the math.

47 x 1 km 0.621

= 75.7 km

Q - How many kilometers are in 47 miles? (note: 1 km = 0.621 miles)

The final answer is 75.7 km

47 x 1 km 0.621

= 75.7 km

SummarySummary

The previous problem was not that hard

In other words, you probably could have done it faster using a different method

However, for harder problems the factor label method is easiest

More examplesMore examples1. You want to buy 100 U.S. dollars. If the

exchange rate is 1 Can$ = 0.65 US$, how much will it cost?

100 US$ x 1 Can$ 0.65 US$

= 153.85 Can$

3. There are 12 inches in a foot, 0.394 inches in a centimeter, and 3 feet in a yard. How many cm are in one yard?

1 yd x 3 ft 1 yd

= 91.37 cmx 12 in

1 ft x 1 cm

0.394 in