Multiplication Shortcut Part 2
Squaring Certain Numbers Let N stands for a number to be squared. If the number ends in 1 or 6: (N – 1) × (N – 1) + (N + N – 1) Example: 91^2 = (91 – 1) × (91 – 1) + (91 + 91 – 1) = 90 × 90 + 91 […]
Monthly Archives: February 2017
Multiplication Shortcut Part- 1
Change Order Numbers may be multiplied in any orders. You can take advantage of this fact by multiplying whatever order is easiest for you. Example: 25 × 937 × 4= 25 × 4 × 937= 100 × 937= 93700 Splitting Number You can simplify multiplication by splitting a number into smaller parts by units (ones), […]
Divisibility Rule
Divisibility Rule for 2 Any even number can be divisible by 2. To find whether a number is even or odd, all we have to do is to check the units (ones) digit. If the units digit is even (0, 2, 4, 6, or 8), then the number is even. 5,345,564 → is divisible by […]
Squaring Shortcuts
Square of multiple of 10 Say, Step 1: Remove the zero part 5 Step 2: Square the remaining digit Step 3: Put this number in front of two zeros 2500 Square a number ending in 5 Say, 95 Step 1: Remove the ending digit 5 95 → 9 Step 2: Add 1 to […]
Quick Way to Divide Multiples of 5 by 5
Divide by 5 When we need to divide any multiple (5, 10, 15, 20, 25, ……..N) of 5 by 5 we can do the division in a quick way: Step 1: Double the multiple Step 2: Divide this by 10 or switch the steps when needed. Example Double the multiple and then divide by 10: […]
Doubling and Halving
Doubling and Halving We can simplify some multiplication problems by doubling one factor and halving the other factor. Example: 500*28 = 1000 * 14 = 14000; 250*48= 500*24= 1000*12= 12000 750*24 = 1500*12 =3000*6= 18000. In the above examples we simplify these multiplication by doubling first number and halving the other number. Still Confusion, just watch the […]
