Big Numbers
ninety-nine trillion, two hundred and forty-six billion, seven million, nine hundred and ninety-nine thousand, one hundred and twenty-three as a number.
99,246,007,999,123
Solve 4 x 2 x 5 x 5 x 2 x 2 using RELOCATION.
4 x 2 x 5 x 5 x 2 x 2
= (2 x 5) x (2 x 5) x (2 x 4)
= 10 x 10 x 8
= 800
Solve 245,172 / 4 using the DIVIDING BY 4 TRICK.
245,172 / 4
Divide by 2 twice.
245,172 / 2 = 122,586
122,586 / 2 = 62,293
= 62,293
six quintillion, thirty-three quadrillion, seventy-two billion, ten million, six hundred and seventy-eight thousand, and one as a number.
6,033,000,072,010,678,001
Solve 30 x 18 by BREAKING UP THE PRODUCT.
30 x 18
= 10 x 3 x 9 x 2
= 10 x 9 x (3 x 2)
= 10 x (9 x 6)
= 10 x 54
= 540
Solve 657,915 / 5 using the DIVIDING BY 5 TRICK.
657,915 / 5
Multiply dividend by 2 and then divide by 10.
657,915 x 2 = 1,315,830
1,315,830 / 10 = 131,583
= 131,583
43,020,010 in words.
forty-three million, twenty thousand, and ten.
Solve 86 x 11 by using THE 11s TRICK.
45 x 11
8 + 6 = 14, therefore middle digit is 4 and the 10 carries over.
First and last digit stay the same (first will increase due to the carry).
= 946
Check if 3,976 is divisible by using the DIVIDING BY 7 TRICK.
Multiply last digit by 2 and subtract from remaining digits. If result is divisible by 7, the original number is, too.
= 397 - (6 x 2)
= 397 - 12
= 385 (can't tell yet, repeat again)
= 38 - (5 x 2)
= 38 - 10
= 28 (divisible by 7)
Yes, 3,976 is divisible by 7!
44,009,876,543,210 in words.
forty-four trillion, nine billion, eight hundred and seventy-six million, five hundred and forty-three thousand, two hundred and ten
Solve 75 x 75 using the TRICK FOR 2-DIGIT SQUARES ENDING IN 5.
75 x 75
7 x 8 = 56, therefore first 2 digits are 56 (tens digit x tens digit+1)
Add 25 to the end.
= 5,625
Solve 490,147 / 7 by BREAKING UP THE DIVISION.
490,147 / 7
490,000 / 7 = 70,000
140 / 7 = 20
7 / 7 = 1
Add above quotients together.
= 70,021
How many zeroes does a Googl have?
100
Solve 69 x 71 using the MULTIPLYING NUMBERS 2 APART TRICK.
69 x 71
= (70 x 70) - 1
= 4,900 - 1
= 4,899
Solve 49,612 / 5 using SHORT DIVISION.
9922 R2
(Take up on the board)