An ant crawls at a speed of 3.5 dm per second. What is the ant's speed in miles per hour? (1 mile is 5280 ft) ( i in = 2.54 cm)

0,783 mile/h

Explanation:

First you convert the dm/s into mile/s:

3,5 dm/s = 35 cm/s, beacause 1 dm = 10 cm, so you calculate 3.5 times 10

→ 3,5 * 10 = 35

35 cm/s = 13,78 in/s, because 1 in = 2,54 cm, so you calculate 35 divided by 2,54 → 35 : 2,45 = 13,78

13,78 in/s = 1,15 ft/s, because 1 ft = 12 in, so you calculate 13,78 divided by 12

→ 13,78 : 12 = 1,15

1,15 ft/s = 0,0002174 mile/s, becaus 1 mile = 5280 ft, so you calculate 1,15 divided by 5280 → 1,15 : 5280 = 0,0002174

Then you convert the mile/s into mile/h:

1 s = 1 / 3600 h

0,0002174 mile/s = 0,0002174 mile : 1/3600 h = 0,0002174 * 3600 mile/h

→ 0,783 mile/h

3 hours because it is a decent distance.