If you want to improve your problem-solving skills and become faster in math, you need to the ways to calculate large numbers without wasting too much time. There are several problem-solving techniques which can help you do your problems faster so that you can focus on bigger concepts instead of wasting time on small calculations. Here are the 5 tricks of doing fast math.
Addition of numbers is the quickest method in math, but it can be even quicker while adding two large number. This method of addition involves bringing the number closest to a multiple of 10. For example, 768+363 will be added below.
Rounding up 768+2=770 and 363+7=370.
Now when we add the rounded up numbers, we get
770+370=1140. Now we determine how much we added to the numbers to round them up, which was 2 and 7. Subtract 2+7=9 from 1140, and we get 1131 which is the answer to 768+363.
Subtracting from 1,000
When you have to subtract from 1000, just subtract single digit in the number from 9 and the last digit from 10. For example, you have to subtract 572 from 1000 then,
So 1000-572 is 428.
Multiplying by 9
When you are multiplying a number with 9, follow these two steps to get a quick answer without memorizing the tables. Let us take the number 8 to multiply with 9. First, we subtract 1 from the 8, which is 8-1=7.
Then we subtract the answer of first subtraction from 9, which is 9-7=2.
The combination of both the number is 72, which is 9 multiplied 8 times.
The division tricks
Division can be very difficult for a lot of students by by ensuring that you complete you math homework on time, you can learn division quicker. Here are the ways to find out if the number is divisible with a number or not.
- Every number is divisible by 1.
- If a number ends with an even digit, it is divisible by 2.
- If the digits of a number are added together to get a 3,6 or 9, it is divisible by 3.
- If a number has two 0s at the end, or the last two digits are evenly divisible by 4, the number is divisible by 4.
- If a number ends with 0 or 5, it is divisible by 5.
- If an even number digits are added together, and the added number is divisible by 3, it is divisible by 6.
- If the last 3 digits of the number are 0s or the last three digits are evenly divisible by 8, the number is divisible by 8.
- If the digits are added together, and the answer is divisible by 9, the number is divisible by 9.
- If the number ends with 0, it is divisible by 10.