what is the easiest way to figure this out without having to go ok 247 x2 = ? , 247 x5 = ? , etc etc. Is there some trick you can use in your head to get in the ball park of the number?
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You can estimate, like this:
247 is about 250.
8491 is about 8500.
250 goes into 1000 four times, so it goes into 8000 eight times as often. 4 * 8 = 32 times.
You're now up to 8000 and have 500 to go, and 250 goes into 500 twice. 32 + 2 = 34, so 250 goes into 8500, 34 times.
Therefore, as an estimate, 247 goes into 8491 about 34 times.
The answer to 8491 / 247 using a calculator is 34.377, rounded to three decimals, so the estimate is pretty close to the exact answer.
247 is about 250.
8491 is about 8500.
250 goes into 1000 four times, so it goes into 8000 eight times as often. 4 * 8 = 32 times.
You're now up to 8000 and have 500 to go, and 250 goes into 500 twice. 32 + 2 = 34, so 250 goes into 8500, 34 times.
Therefore, as an estimate, 247 goes into 8491 about 34 times.
The answer to 8491 / 247 using a calculator is 34.377, rounded to three decimals, so the estimate is pretty close to the exact answer.
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Don't know the old ways do you grasshopper?
Get a piece of paper and a pencil (yellow thing-sharp point one end).
Now write down the number 8491 - draw a division bracket over it. Write the 247 on the outside of the bracket.
Now...do some work. You start with what you know- that 1X247 is too low, and 10X247 is too high. Somewhere in the middle is your number.
Good luck. And remember, one of these days when the power goes off and your calculator, phone and computer do not work, you will be a powerful person in the new world because you can do math without any mechanical help.
Who knows, you might be the ruler of the world!!
Get a piece of paper and a pencil (yellow thing-sharp point one end).
Now write down the number 8491 - draw a division bracket over it. Write the 247 on the outside of the bracket.
Now...do some work. You start with what you know- that 1X247 is too low, and 10X247 is too high. Somewhere in the middle is your number.
Good luck. And remember, one of these days when the power goes off and your calculator, phone and computer do not work, you will be a powerful person in the new world because you can do math without any mechanical help.
Who knows, you might be the ruler of the world!!
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i usually round up to a number i can easily do in my head ( like 250)
so then 250 goes into 1000 = 4 times
250 goes into 8000= 32 times
250 goes into 8491 = 33 times
33 should be pretty accurate, but the answer is actually 34 and a bit
this is because we added 3 to 247 and dealt with 250 (so you could have made up for that by adding 1 to our inital calculation of 33)
so then 250 goes into 1000 = 4 times
250 goes into 8000= 32 times
250 goes into 8491 = 33 times
33 should be pretty accurate, but the answer is actually 34 and a bit
this is because we added 3 to 247 and dealt with 250 (so you could have made up for that by adding 1 to our inital calculation of 33)
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First, round 247 up to 250, and 8,491 to 8,500. Then knowing that 250 goes into 1,000 four times, you should be able to calculate that 247 goes into 8,000 32 times. (4 x 8 = 32). Then, you can add 2 to 32 because 250 goes into 500 twice. 247 goes into 8,491 about 34 times.
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well 247 is close to 250 right?. 8591 is about 8500, 8500 / 250 = 34. so its around 34. ( it actually is 34 plus a remainder, since using this you are overestimating 247 by 3 each time: 3* 34 = 102, so that means 247 * 34 = 8500 - 102, which is 8398 < 8491, so we didn't go over the actual answer.
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Well I'd round 247 to 250 and round 8491 to 8500 and then I know that 4x250 is 1000 and there are 8 1000s. So you multiply 4 by 8 to get 32 and add on the last 2 250s to get the last 500. So that means 247 goes into 8491 approximately 34 times.
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long division takes seconds. It actually takes longer to try to estimate the answer than it does to just do the long division.
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If you just want to get an idea of what might work, say in doing long division, round of both numbers, so 200 and 8000, or about 40 times.