SOLUTION: Please help me solve: Stephen gave four-fifths of his pencils to Brittany; then he gave two-thirds of the remaining pencils to Jennifer. If he ended up with ten pencils for himself

Question 641810: Please help me solve: Stephen gave four-fifths of his pencils to Brittany; then he gave two-thirds of the remaining pencils to Jennifer. If he ended up with ten pencils for himself, with how many did he start?
I am an adult non-traditional student who has always struggled in Math, especially word problems. I just need to know where to start. If you could walk me through the steps, I would greatly appreciate your help.
Answer by General_Lee87(58) (Show Source): You can put this solution on YOUR website!
Origional problem: Stephen gave four-fifths of his pencils to Brittany; then he gave two-thirds of the remaining pencils to Jennifer. If he ended up with ten pencils for himself, with how many did he start?
Solution: 150 x 4/5 = 120
150 - 120 = 30
30 x 2/3 = 20
30 - 20 = 10
I randomly found the number 150 by using my famous guess and check system. I just do the whole problem with random numbers until I get close and then find the number needed. It took me a few tries on a calculator, but I figured it out. First you take 150 pencils and multiply it by 4/5. You get 120 and then subtract it from the origional numer, 150, to get 30. Next, you take your remaining 30 pencils and multiply them by 2/3 to get 20. You then subtract 20 from 30 to get your 10 remaining pencils. I hope this helped. Good luck and best wishes.
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