Last Year the price per share of Company A's stock on March 31 was 25

We are given that last year the price per share of Company A's stock on March 31 was 25 percent higher than its price per share on March 1, and that by April 30 the stock's price per share was 20 percent lower than the price per share on March 1.

If we let p = the price per share of Company A’s stock on March 1, we can create the following equations:

price on March 31st = 1.25p
price on April 30th = 0.8p

We need to determine the percent decrease in price per share of the stock from March 31st to April 30th. We can use the percent change equation:

Percent change = (new - old)/old x 100

Percent decrease = [(0.8p - 1.25p)/(1.25p)] x 100

Percent decrease = [(80p - 125p)/(125p)] x 100

Percent decrease = [(-45p)/(125p)] x 100

Percent decrease = (-9/25) x 100 = -9 x 4 = -36

Thus, there was a 36 percent decrease in price per share.

Answer: C

In order to avoid repeated mistakes use numerical values and be systematic

Let the price per share on March 1 be 100

It is 25% greater than this on March 31 So 125

Price on April 30 is 20 % less than that on March 1 So 80

Percentage decrease from March 31 to April 30 = {( 125-80)/125 } * 100 = 36%

Let the value at march 1st be 100.
By 31st March it increased by 25% making it 125.

But from March 1st to April 30th, the value decreased by 20% making the final value on April 30th as 80.
hence, we need to find the decrease from March 31st to April 30, which will be provided by-
[(125-80)/125]*100= 36%

The answer is C

Last Year the price per share of Company A's stock on March 31 was 25 percent higher than its price per share on March 1. By April 30 the stock's price per share was 20 percent lower than the price per share on March 1. What was the percent decrease in price per share of the stock from March 31 to April 30?

A. 5%
B. 25%
C. 36%
D. 45%
E. 56%

Solution:-
Let Price on 1st Marach-100
On 31 marach it was -125
on april it -80
Total decrease in price -125-80=45
%decrease=45/125*100
=45*4/5
=36%

Let the price of stock on March 1 be x
Then the price of stock on March 31 = 1.25x
and the price of stock on April 30 = 0.8x

% decrease = (Price of stock on march 31 - price of stock on april 30)/Price of stock on march 31
= (1.25x-0.8x)/1.25x
= 36%

Hence C

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