A: What decimal is equivalent to 72/100? Well, 72/100 means you have 72 out of 100. Meaning it's not a whole number, so this means as a decimal, your answer would be behind the decimal point. Behind the decimal, you have 3 main places. Tenths, Hundredths, and Thousandths. It goes much further than that, of course, but most don't have to worry about those. 72/100 is represented as 72-hundredths, or .72 You are correct.
B: .72 as a fraction is 72/100. Simply divide by 2 until you simply can't anymore, this saves you time. 72/100 divided by 2 equally is 36/50. This divided by 2 equally is 18/25. This is the lowest form, you are correct.
C: Well, also simple. We know that when you have an exponent, you multiply the number by itself. 9^2 is 81, because 9*9=81. HOWEVER, this applies to only positive exponents. With negative exponents, you have to make it a fraction as 1. So, your answer is indeed 1/81
Please see below solution: Let x = number of books that Bryan reads2x for amanda = Amanda 3x - 4 for Colin Amanda = 5/8(Bryan + Colin)2x = 5/8(x+3x-4)2x = 5/8(4x-4)
[16x = 5(4x-4)]816x = 20x - 20Subtract 20x from each side-4x =-20-4x/-4= -20/-4 divide -4 to eliminate the -4 in -4xx = 5 Therefore: Bryan reads 5 books a month. Since Amanda reads twice as many books a Bryan read so Amanda 10 books a month. And Colin 11 books a month. 3(5) - 4 = 11
The ladder is the hypotenuse, the wall is one of the legs. In order to find the other leg you have to do c^2-a^2=b^2. 41^2-40^2 is 81 and the square root of that is 9
