SOLUTION: A 20-lb bag cement mix contains 25% cement. How many pounds of pure cement must be added to the mixture in order to get 40% cement?
Algebra.Com
Question 903288: A 20-lb bag cement mix contains 25% cement. How many pounds of pure cement must be added to the mixture in order to get 40% cement?
Answer by richwmiller(17219) (Show Source): You can put this solution on YOUR website!
1*x+0.25*20=0.4(20+x)
1*x+5=8+0.4x
1x-0.4x=8-5
0.6x=3
x=5 lbs of 100% is added to 20 lbs of 25% to get 25 lbs at 40%
check
1*5+0.25*20=0.4(20+5)
5+5=0.4(25)
10=10
ok
RELATED QUESTIONS
a 20-lb bag of cement contains 25% cement and 75% sand. How much pure cement must be... (answered by josgarithmetic)
Cement Mix:
A 20-pound bag of Economy brand cement mix contains 25% cement and 75%... (answered by stanbon)
A 20-pound bag of Economy brand cement mix contains 25% cement and 75% sand. How much... (answered by ikleyn,MathTherapy)
a 30 lb bag of cement contains 35% cement and 65% sand. how much pure cement must be... (answered by LinnW)
A 20-pound bag of Economy brand cement mix contains 25% cement and 75% sand. How much... (answered by josgarithmetic,greenestamps,ikleyn)
Dearest tutors, can you help me regarding my problem? thank you for that..
4. A... (answered by stanbon)
2. A mixture contains 6 kg sand and 4 kg of cement. How much cement must be added to kema (answered by harpazo)
a 50 pound bag of a cement-sand mixture is 40% sand. How many pounds of pure 100% sand... (answered by josgarithmetic)
An engineer wants to make a 40% cement mixture. How many pounds of a 60% cement mixture (answered by stanbon)