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Estimating with multiplying decimals and whole numbers

Learn all about the concept of estimating products in multiplication problems involving decimals and whole numbers. Understand the importance of rounding to the nearest whole number for easier computation, and demonstrates how this strategy can help make reasonable estimates. Created by Sal Khan.

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• ok so estimating is pretty easy, but what about doing without estimating and multiplying them. how can that happen?
• Good question. It's basically the same thing as multiplying whole numbers, and I am sure that this will be covered in a future lesson. Just pretend like the decimal isn't there until you get your answer. Then, add the number of digits after the decimal in each factor (A factor is one of the numbers that you multiply by in a multiplication problem.) You then move the decimal point that many places in the answer (In a whole number, the decimal point is at the end, you just don't usually draw it.)

To whom this may concern,
Hope this helps. :)
(1 vote)
• Yeah I got confused to
• Okay, you can call me SNOW, lets say we have to estimate 2.9*6 and our answers that we can choose from are A 16, B 160, C 1,600, and D 16,000. First we would first we have to round 2.9, so if we round 2.9 it looks we can turn the 2 from 2.9 into a 3 so it would be 3*6 and 3*6= 18 and you see we don't have 18 as a answer below see(A 16, B 160, C 1,600, and D 16,000)the closes one to 18 wound be(A 16)it is closer to 18 then any other answer so it would be(A 16)that is a example of estimating.

hope this helps😄
SNOW OUT!
(1 vote)
• Can someone explain to me what this means
• Okay, you can call me SNOW, lets say we have to estimate 2.9*6 and our answers that we can choose from are A 16, B 160, C 1,600, and D 16,000. First we would first we have to round 2.9, so if we round 2.9 it looks we can turn the 2 from 2.9 into a 3 so it would be 3*6 and 3*6= 18 and you see we don't have 18 as a answer below see(A 16, B 160, C 1,600, and D 16,000)the closes one to 18 wound be(A 16)it is closer to 18 then any other answer so it would be(A 16)that is a example of estimating.

hope this helps😄
SNOW OUT!
(1 vote)
• how do you estimate
(1 vote)
• Okay, you can call me SNOW, lets say we have to estimate 2.9*6 and our answers that we can choose from are A 16, B 160, C 1,600, and D 16,000. First we would first we have to round 2.9, so if we round 2.9 it looks we can turn the 2 from 2.9 into a 3 so it would be 3*6 and 3*6= 18 and you see we don't have 18 as a answer below see(A 16, B 160, C 1,600, and D 16,000)the closes one to 18 wound be(A 16)it is closer to 18 then any other answer so it would be(A 16)that is a example of estimating.

hope this helps😄
SNOW OUT!
(1 vote)
• friday its me yoda
(1 vote)
• For some reason I keep getting stuck on multiplying and dividing fractions! Like, at its confuseing but maybe it'll be answered in the vid?

*how do you multiply fraction times decimal? I forgot**
• You basically just do it the same way, but remember there different.
(1 vote)
• They said sixteen hundred but its one thousand six hundred- what do they mean- this is also quiet confusing but i might be able to understand a lil