The united states consumes 2.6 billion cases of bottled water per year. assume that each case holds 24 ½-liter bottles. each case is 10.2 inches tall, 15.1 inches long and 8.3 inches wide.
if all of these cases were lined up end-to-end at the equator, how many times would they go around the earth? what would be the perimeter and area of the base of all of these cases together? the volume?
note: the circumference of the earth’s equator is 24,901 miles. 1 mile = 5280 feet

So first find the circumfernece of the earth which is 24,901 times 5280 
use a calculator 
24,901 times 5280=131,477,280ft
1 ft=12 inches so 131,477,280 times 12=157,727,360 in
so 157,727,360 divide by the legnth of the case=1,577,727,360/15.1=104,485,255.62914 cases to go around the earth once so 
million=1000 thousand
billion=1000 million
billion=1,000,000,000
2.6 billion=2,600,000,000
so 2,600,000,000/104,458,255.62914=24.88 or rounded up they would go around the earth close to 25 times

AREA OF THE BASES
base=legnth times width so 15.1 times 8.3 =125.33 in^2
multiply 125.33 in^2 by 2,600,000,000 and get 325,858,000,000 in^2 or 3.25858 times 10^11=area of the bases

PERIMETER OF THE BASES
perimeter of the bases 2Legnth+2Width times 2.6 billion
2(15.1)+2(8.3)=46.8
46.8 times 2.6 billion=121,680,000,000 inches  or 1.2168 times 10^11= perimeter of all the bases

VOLUME
24 1/2 liter bottles means 24 times 1/2=12 liters in each pack 
2.6 billion times 12=31,200,000,000 liters or 3.12 times 10^10

143 75 107 13 the answer