A baseball card decreased in value 20% in its first year and 10% in it

Question

A baseball card decreased in value 20% in its first year and 10% in its second year. What was the total percent decrease of the card's value over the two years?

A. 28%
B. 30%
C. 32%
D. 36%
E. 72%

Skywalker18 · Answer

Let the initial value of baseball card = 100
After first year , value of baseball card = (1- 20/100)* 100 = 80
After second year , value of baseball card =(1 - 10/100)* 80 = 72

total percent decrease of the card's value over the two years = (100-72)/100 *100%
=28%
Answer A

rhine29388 · Answer

consider the initial value of the baseball card as $100
After first year price = 100*0.8 = 80
After second year price = 80 *0.9 = 72
final decrease =   * 100 = 28%
correct answer - A

TeamGMATIFY · Answer

Method 1: Formula for successive percentage decrease/increase
 If there is a decrease of a and b percent for 2 years, we can use
Total percentage decrease = - a - b + (ab/100)
The sign of a and b can change corresponding to an increase/decrease.
+ sign for increase and - sign for decrease.

Putting the values, total decrease = - 20 - 10 + 2 = -28
Or 28% decrease. 
Option A

Method 2:
Assume the initial value = 100
Value after first decrease = 80
Value after second decrease = 72
Hence total decrease = 100 - 72 = 28%
Option A

JeffTargetTestPrep · Answer

In two years the card is worth 0.8 x 0.9 = 0.72 = 72% of its original value, which is a 28% decrease from its original value.

Answer: A

SAMARjack123 · Answer

we can use two different approaches for this question which is suitable for you. first i used is algebra, i always love that because it is efficient and suitable for me.

i assumed card=x then x*20/100=0.2X then we have to subtract how much we get x-0.2x=x(1-0.2)=0.8x. then 0.8x*10/100=0.08x. then find total decrease that means 0.2x+0.08x=x(0.28).

we can divide by original card value. when we divide by original card. then will get 0.28. then to find percentage multiply with 100. so 28%.

there is another approach arithmetic.

we can assume card=100

then 100*20/100=20. then the remaining value is 100-20=80.

then 80*10/100= 8. then total 8+20=28. to convert percentage multiply with 100.

so, 28%.

with love,
samar jack

A baseball card decreased in value 20% in its first year and 10% in it

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