SOLUTION: 3/5 of the number of pens displayed at the bookstore were red and the rest were blue.After 260 red pens, and 1/4 of the blue pens were sold, 1/2 of the pens were left.How many pens
Question 1141187: 3/5 of the number of pens displayed at the bookstore were red and the rest were blue.After 260 red pens, and 1/4 of the blue pens were sold, 1/2 of the pens were left.How many pens were displayed at the bookstore first?
Can you please help me how to solve this by equation??
Thanks in advance Found 3 solutions by josgarithmetic, rothauserc, ankor@dixie-net.com:Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website! p, total number of pens at the start
RED BLUE
Initial
Final
Total
Solve the TOTAL equation for p.
Answer by rothauserc(4718) (Show Source): You can put this solution on YOUR website! let x be the number of pens displayed at the bookstore first
:
3x/5 are red, 2x/5 are blue
:
260 + (2x/5)/4 = x/2
:
260 + (2x/20) = x/2
:
5200 +2x = 20x/2
:
10400 +4x = 20x
:
16x = 10400
:
x = 650
:
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there were 650 pens at first
:
check the answer
:
there are 390 red at first and 260 blue at first
:
260 + (260/4) = (650/2)
:
260 + 65 = 325
:
325 = 325
:
answer checks
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: Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website! 3/5 of the number of pens displayed at the bookstore were red and the rest were blue.
let p = total no. of pens
then p = no. of red pens
and p = no. of blue
:
After 260 red pens, and 1/4 of the blue pens were sold, 1/2 of the pens were left.
260 + *p = p
260 + = p
reduce fraction
260 + p = p
get rid of denominator, multiply by 10
2600 + p = 5p
2600 = 5p - p
2600 = 4p
p = 2600/4
p = 650
:
How many pens were displayed at the bookstore first? 650