Answer:
a) 43
b) 5.7
c) 2.54
Explanation:
The metric system is so easy to work with, everything is in base of 10, and all measures use a prefix. Here, we're talking about length, with the main measure being the meter.
1 m = 100 centimeters (centi- = 1/100)
1 m = 1000 millimeters (milli- = 1/1000)
So, for each centimeter, you have 10 millimeters.
a) How many millimeters are in 4.3 centimeters?
1 cm = 10 mm as shown above, so 4.3 cm = 43 mm
b) How many centimeters are in 57 millimeters?
10 mm = 1 cm so, 57 mm = 5.7 cm
c) Approximately how many centimeters are in an inch?
There are approximately 2.54 cm in an inch. No real calculation to make here, it's just a unit conversion between systems, done following a known reference table.