The quantities in the proportion you give add to 16 pounds, of which 2 pounds are cement. That is, cement constitutes 1/8 of the total weight.
For each yard of concrete, 4000 lb/8 = 500 lb of cement are used.
For 12.5 yards of concrete, 12.5 * 500 = 6,250 pounds of cement will be used.
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"yard" in this case is shorthand for "cubic yard".
I all of those options are true
Integer generally means number.
if s = seconds then
2s = 18
solve for s,
18/2 = 7
s = 7 seconds
Factors of 10 are : 1,2,5,10
To find the total mass you will add the following masses together:
1/4 + 1/4 + 2/4 + 2/4 + 2/4 + 3/4 + 3/4
For every X you list the number that many times.
The sum is 14/4 or 3 2/4 or
3 1/2.
The answer is choice D.