There are 2.54 centimeters in an inch how many inches are in 51.78 centimeters round to the nearest tenths

2.54 cm in 1 inch ... how many inches in 51.78 cm ...

51.78 / 2.54 = 20.4 inches <==

or this way ...

2.54 / 1 = 51.78 / x ... 2.54 cm to 1 in = 51.78 cm to x inches

cross multiply

(2.54) (x) = 51.78) (1)

2.54x = 51.78

x = 51.78 / 2.54

x = 20.4 inches <==