SOLUTION: Lucy must shovel a pile containing 50 ft3 of sand into a dump truck. With each scoop she decreases the size of the pile by 1/6 ft3. Let "X" be the number of scoops she has shovele

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Lucy must shovel a pile containing 50 ft3 of sand into a dump truck. With each scoop she decreases the size of the pile by 1/6 ft3. Let "X" be the number of scoops she has shovele      Log On


   

Question 490152: Lucy must shovel a pile containing 50 ft3 of sand into a dump truck. With each scoop she decreases the size of the pile by 1/6 ft3. Let "X" be the number of scoops she has shoveled.
A) Write an expression for the number of cubic feet of sand left in the pile after "X" scoops
B) How much sand is left after 12 scoops?
C) Lucy takes a rest when 20 ft3 of sand REMAINED, write an equation stating that 20 ft cubed remained, then solve the equation to find out how many scoops Lucy shoveled before she rests.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The number of cubic feet of sand left in the pile after "X" scoops is:
a)
+50+-+%281%2F6%29%2Ax+ ft3
b)
+50+-+%281%2F6%29%2A12+=+48+ ft3
c)
20 ft3 remained
+20+=+50+-+%281%2F6%29%2Ax+
Subtract +50+ from both sides
+-30+=+-%281%2F6%29%2Ax+
Multiply both sides by -1
+%281%2F6%29%2Ax+=+30+
+x+=+180+
She shoveled 180 scoops before resting