Math Magic - Dividing by 40


HOME Miscellaneous Elementary GCD LCM Definitions Percents Ratios Square Roots Reverses Junior High Cube Roots Mult By 9 (#1) Mult By 9 (#2) Mult By 8 Polynomials Positive Integral Divisors Sum Of Positive Integral Divisors Relatively Prime Triangular Numbers Remainders Divide By 40 Divide By 25 Divide By 9 High School Pentagonal Numbers Hexagonal Numbers Heptagonal Numbers Octagonal Numbers Manipulating Polygonal Numbers Dividing Factorials #1 Dividing Factorials #2 Solving Triangular Numbers		(View/Download .pdf file) Dividing By 40 Into Decimal/Percent: A. Dividing by 40 into a decimal or a percent is easy since: n ₌ 25n 40 1000 B. Therefore, we can multiply by 25 and divide by 1000. Ex [1] ³/₄₀ = __________(decimal). a. Multiply 3 x 25 we get 75. b. 75 / 1000 = .075. c. The answer is .075 Ex [2] ³¹/₄₀ = __________(percent). a. 31 x 25 = 775. b. 775 / 1000 = .775. c. As a percent this is 77.5%. d. The answer is 77.5.