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# Simple percentage question

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1. Hi, so i'm about to embarrass myself here.

I have 2 questions on an exam.

1) X has increased 1% to 2,537. What was the value of X originally?

2) X has decreased by 9% to 1,586. What was the value of X originally?

I did question 1) as follows (so you can see my working):

X + 0.01X = 2537
1.01X = 2537
X= 2537 / 1.01 = 2511.88

2511.88 has increased 1% to 2537.

How do I do a decrease calculation?? Obviously if I follow the same logic I get a lower number, I need a higher one...
2. (Original post by aewart)
Hi, so i'm about to embarrass myself here.

I have 2 questions on an exam.

1) X has increased 1% to 2,537. What was the value of X originally?

2) X has decreased by 9% to 1,586. What was the value of X originally?

I did question 1) as follows (so you can see my working):

X + 0.01X = 2537
1.01X = 2537
X= 2537 / 1.01 = 2511.88

2511.88 has increased 1% to 2537.

How do I do a decrease calculation?? Obviously if I follow the same logic I get a lower number, I need a higher one...
1 is correct
3. (Original post by aewart)
Hi, so i'm about to embarrass myself here.

I have 2 questions on an exam.

1) X has increased 1% to 2,537. What was the value of X originally?

2) X has decreased by 9% to 1,586. What was the value of X originally?

I did question 1) as follows (so you can see my working):

X + 0.01X = 2537
1.01X = 2537
X= 2537 / 1.01 = 2511.88

2511.88 has increased 1% to 2537.

How do I do a decrease calculation?? Obviously if I follow the same logic I get a lower number, I need a higher one...
You do follow the same logic

x - 0.09x =1586

4. (Original post by TenOfThem)
You do follow the same logic

x - 0.09x =1586

Boom, done! Thanks!

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