In January, Mr Tan's students read 20 books. In Febuary, they read 15 books. What is the percent increase or decrease in the number of books they read? A. 5% decrease
B. 15% increase
C. 25% increase
D. 25% decrease​

25% Decrease

Step-by-step explanation:15/20 is 75%. 100-75 (since they read less) is 25%

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try looking in the very back of the book : )

step-by-step explanation:

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the answer is b: 18

step-by-step explanation:

use the pythagorean theorem to .

a^2+b^2=c^2

plug 18 for "r"

the 2 legs are 18 and 24

18^2+24^2=c^2

324+576=c^2

900=c^2

c=30

30-12=18

18 is the radius

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