The no of library books in a school increased by 20% after it bought new books in May , the number increased by another 20% after a book store donated 300 books in June - Find the no of books in library before it bought new books in May

n = original

1.2 n = before 300

.2 * 1.2 n = 300
so
1.2 n = 1500
n = 1250 books originally

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check
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1.2 * 1250 = 1500
+300 = 1800
1.2*1.2*1250 = 1800 sure enough

Let's assume the number of books in the library before it bought new books in May is 'x'.

After purchasing new books in May, the number of books increased by 20%, which means there are (x + 0.2x) books in the library now.

Simplifying, (1 + 0.2)x = 1.2x books in the library after buying new books in May.

After the book store donation in June, the number of books increased by another 20%, which means there are 1.2x + (0.2)(1.2x) = 1.2x + 0.24x books in the library now.

Simplifying, 1.44x = 1.44x + 300 books in the library after the donation in June.

Since there is an increase of 300 books after the donation, we can solve for 'x' in the equation 1.44x = 1.44x + 300.

Subtracting 1.44x from both sides, we get 0 = 300.

Since we have arrived at an absurd equation, there is no solution that satisfies the given scenario.

To find the number of books in the library before it bought new books in May, we can use the following steps:

Step 1: Let's assume the initial number of books in the library before May is "x".

Step 2: In May, the number of books increased by 20%. Therefore, the number of books in May can be calculated as:
Number of books in May = x + (20/100) * x

Step 3: In June, after the bookstore donated 300 books, the number of books increased by another 20%. Therefore, the number of books in June can be calculated as:
Number of books in June = (x + (20/100) * x) + 300 + (20/100) * (x + (20/100) * x)

Step 4: Since we want to find the number of books in the library before it bought new books in May, we need to subtract the donated books and the percentage increase in June. Therefore, we can set up the equation:
x = Number of books in June - 300 - (20/100) * (x + (20/100) * x)

Step 5: Solve the equation to find the value of x, which is the initial number of books in the library.

Let's simplify and solve the equation:

x = ((x + (20/100) * x) + 300 + (20/100) * (x + (20/100) * x)) - 300 - (20/100) * (x + (20/100) * x)

Simplifying further:

x = x + (20/100) * x + 300 + (20/100) * x + 300 - 300 - (20/100) * (x + (20/100) * x)

x = x + 0.2x + 300 + 0.2x + 0.2(0.2x)

x = x + 0.2x + 300 + 0.2x + 0.04x

x - x - 0.2x - 0.2x - 0.04x = 300

-0.04x = 300

Dividing both sides of the equation by -0.04:

x = 300 / -0.04

x = -7500

Therefore, the initial number of books in the library before it bought new books in May is -7500.

Note: There seems to be an error in the calculations, as the number of books cannot be negative. Please double-check the information provided or clarify any additional details if available.