1 x 423 | 3 x 141 | 9 x 47
I round one of the numbers (usually the larger one but either one works) up or down to the nearest number that is easy to multiply in my head. Like this: 423 x 12 Becomes: 425 x 12 Then I would say that if 425 x 12 = ___, then 850 x 6 = ____ too. Because 850 = 425 x 2 and 6 = 12 / 2 And if 850 x 6 = ____, then 1700 X 3 = ____ also. 1700 x 3 = (1000 x 3) + (700 x 3) = 3000 + 2100 = 5100 So, 425 x 12 = 5100. But, we started with 423 not 425. (425 x 12) - ((425-423) x 12) = 423 x 12 425 - 423 = 2 So, we need to multiply the difference (2) by 12 and subtract that from the 5100 to get the real answer. 2 x 12 = 24 5100 - 24 = 5100 - 25 + 1 = 5076 423 x 12 = 5076 Ta Da! Another way, is to break one into easy to use numbers (12 is good for this) and skip the rounding step. But, sometimes there is no easy split (3746 x 5317) and then the rounding works better. But, here is the split method (I also used it above.) 423 x 12 = (423 x 10) + 423 x 2 423 x 10 = 4230 and 423 x 2 = 846 4230 + 846 = 5076 With practice you will get faster at this and you will even be able to hold a conversation while doing the math. Then everyone will think you are a genius!
2000
42 x 3 = 126
200 x 200= 40,000
x + 2x + 423 = 3x + 423
423 141,3 47,3,3 3 x 3 x 47 = 423
x + 361 = 555 + 423 x = 555 + 423 - 361 x = 617
The prime factors of 423 are: 3 x 3 x 47
3 x 3 x 47 = 423
3 x 3 x 47 = 423
1, 3, 9, 47, 141, 423: (1 x 423, 3 x 141, 9 x 47)
1 x 423 | 3 x 141 | 9 x 47
48,395 multiplied by 423 = 20,471,085
1 x 423, 3 x 141, 9 x 47.
It is x + 423. There is no equation nor an inequality that can be solved for the value of x. It is simply an expression.
423 is a composite number. Its prime factorisation is 3 x 3 x 47.