- #1
Jekertee
- 43
- 0
How to do this in 10 seconds without a calculator and scratch paper?
1565 x 1197 = ?
1565 x 1197 = ?
Jekertee said:How to do this in 10 seconds without a calculator and scratch paper?
1565 x 1197 = ?
jimmysnyder said:...
Jekertee, are you willing to teach us the method?
Jekertee said:...I input random numbers into the search box of google but found only strange result.
Is there any information you could give us to help search for it?Jekertee said:I din't know that method also, I made a quizz thinking that someone knew to tell me too
Yes, here's a proof. Let a be the common tens place digit (2 in this case), and b one of the ones place digits (either 3, or 7 in this case). Thennabeelr said:when multiplying 2, 2-digit numbers with the same tens digits and two ones digits that add up to 10, (ex. 23 x 27 ) the vedic stuff is useful.
you just multiply the tens digit by the next number up, so multiply 2 by 3 and get 6.
then multiply the two ones digits, and get 21.
the answer is 621.
It is possible to do multiplication quickly without a calculator or paper by using mental math strategies and tricks. With practice, one can develop the ability to quickly estimate and solve multiplication problems in their head.
One popular trick for multiplying large numbers quickly is the "split and multiply" method. This involves breaking down the numbers into smaller, easier-to-multiply parts and then adding the products together.
Sure, let's take 1565 and 1197 as an example. First, we can break down 1565 into 1500 + 60 + 5, and 1197 into 1100 + 90 + 7. Then, we can multiply each part and add them together: (1500 x 1100) + (1500 x 90) + (1500 x 7) + (60 x 1100) + (60 x 90) + (60 x 7) + (5 x 1100) + (5 x 90) + (5 x 7) = 1650000 + 135000 + 10500 + 66000 + 5400 + 420 + 5500 + 450 + 35 = 1863905.
Yes, there are several other strategies such as the lattice method, the Russian peasant method, and the grid method. These methods involve breaking down the numbers into smaller parts and using visual patterns to solve the problem.
The best way to improve mental math skills for multiplication is through practice. Start by practicing with smaller numbers and gradually work your way up to larger numbers. Also, try to memorize common multiplication facts to make the process faster. Additionally, there are many online resources and apps available for mental math practice.