Pens cost 70 cents each and pencils cost 40 cents each. If Iris spent

Question

Pens cost 70 cents each and pencils cost 40 cents each. If Iris spent $5.20 on a total of 10 pens and pencils, how many pencils did she purchase? ($1 = 100 cents)

(A) 4
(B) 6
(C) 8
(D) 10
(E) 13

EgmatQuantExpert · Answer

Solution

Given:  
 • Each pen costs 70 cents
• Each pencil costs 40 cents
• Iris spent $5.20 on a total of 10 pens and pencils

To find:  
 • The number of pencils did Iris purchase

Approach and Working:  
If we assume that Iris purchased n pencils, then
 • Number of pens that she purchased = 10 – n

As she spent $5.20 in total, we can write
 • 70 (10 – n) + 40 n = 520
Or, 700 – 70n + 40n = 520
Or, 30n = 180
Or, n = 6

Hence, the correct answer is option B.

Answer: B

magbot · Answer

Pens (x) + Pencil (y) = 10 -> eq (1)
70x + 40y = 520 -> eq(2)
----------------------

70x + 40y = 520
-40x - 40y = -400 (Multiply eq(1) with -40 on both sides ) 
--------------------------
30x = 120
x = 4

sub x in eq(1) and hence y = 6

Answer: B

JeffTargetTestPrep · Answer

We can let the number of pens = n and the number of pencils = c and create the equations:

70n + 40c = 520

and

n + c = 10

Simplifying the first equation, we have 7n + 4c = 52, and multiplying the second equation by 7, we have 7n + 7c = 70. Subtracting these two new equations, we have:

-3c = -18

c = 6

Answer: B

MBAHOUSE · Answer

Pens cost 70 cents each and pencils cost 40 cents each. If Iris spent $5.20 on a total of 10 pens and pencils, how many pencils did she purchase? ($1 = 100 cents)

(A) 4
(B) 6
(C) 8
(D) 10
(E) 13

bumpbot · Answer

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Pens cost 70 cents each and pencils cost 40 cents each. If Iris spent

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