Question

The average distance of the sun from Earth is about 1.5 x 108 kilometers.

If the thickness of a quarter is 1.5 millimeter, how many quarters do
you need to stack to reach the sun? A kilometer is equal to a million
millimeters.
a. 102 million
c. 104 billion
b. 105 billion
d. 106 billion

Answer 1

10⁵ billion

Explanation:

given that distance from sun to earth

= 1.5 x 10⁸ km (we need to convert this to millimeters)

= 1.5 x 10⁸ km x 1 million mm per km

= 1.5 x 10⁸ km x 1,000,000 mm/km

= 1.5 x 10⁸ km x 10⁶ mm/km

= 1.5 x 10⁸ x 10⁶

= 1.5 x 10⁽⁸ ⁺ ⁶⁾

= 1.5 x 10¹⁴ mm

also given that a quarter is 1.5mm thick, hence the number of quarters that will span the distance between the sun an earth (i.e 1.5 x 10¹⁴ mm)

= 1.5 x 10¹⁴ mm ÷ 1.5 mm/quarter

= 10¹⁴

= 100,000,000,000,000 (remember that a billion has 9 zeros)

= 100,000 billion

= 10⁵ billion