Estimate the following products using general rule:
(a) 578 × 161 (b) 5281 × 3491 (c) 1291 × 592 (d) 9250 × 29
Solution (a)
578 x 161
Rounding off 578 to the nearest hundreds, we get 600
And, rounding off 161 to the nearest hundreds, we get 200
Therefore, 600 x 200 = 1,20,000
It means that estimate of 578 x 161 is equal to 1,20,000 according to the general rule.
Solution (b)
5281 × 3491
Rounding off 5,291 to the nearest thousands, we get 5,000
And, rounding off 3,491 to the nearest hundreds, we get 3,500
Therefore, 5,000 x 3,500 = 1,75,00,000
It means that estimate of 5281 x 3491 is equal to 1,75,00,000 according to the general rule.
Solution (c)
1291 × 592
Rounding off 1291 to the nearest hundreds we get, 1300
And, rounding off 592 to the nearest hundreds, we get 600
Therefore, 1300 x 600 = 7,80,000
It means that estimate of 1291 x 592 is equal to 7,80,000 according to the general rule.
Solution (d)
9250 × 29
Rounding off 9250 to the nearest thousands, we get 9000
And, rounding off 29 to the nearest tens, we get 30
Therefore, 9000 x 30 = 2,70,000
It means that estimate of 9250 × 29 is equal to 2,70,000 using general rule.
SHANOJ A JOY says
5281 × 3491
can i do this
5300 X 3500 or
5300 x 3000 or
5000 x 3000
Sumedha says
As we were told that the general rule is to round off the number to its greatest place… According to that
5281 x 3491
5000 x 3000
=15000000
Similarly
1291 x 592
1000 x 600
=600000
Rajesh says
अगर हम 5281 का नजदीकी 5000 मानते हैं तो 3481 का 3000 क्यों नहीं
Gaurav says
Same question I also want answer of this question ..Why ???
Almas says
Kyu ki 3481 ke third digit me 8 h isiliye
Yogendra says
जब हम 3491 -> 100 से estimate करते हैं, तब 100 में 2 -> zero होता है तो हम tens के place पर देखेंगे तो उधर 9 लिखा रहता है जिससे 3941 -> 3500 बन जाता हैं ।
Rekha says
Yes you are correct
Swastik priyadarshi says
Cano you tell me these answer 9×795
Yogendra says
795
× 9
—–
7155 ]- 795*9 का उत्तर 7155 है ।
Abhinav Anish says
5000 × 3000
Gayathri Krishnan says
I am studying in narayana school in vizag my sir said di this for he I don’t how to do
This is very helpful full for
Bhumi Bansal says
Very good l am finding answer and I got it thanks
ajay says
6767*2016
Yogendra says
6767
× 2016
———-
40602
+ 6767 X
+ 3534XXX
———-
6342272 ]- 6767*2016=6342272
Vikas G Sharma says
9250×29 ‘s answer given in our book is 300000 but U give the answer 270000 ..whose one is right….?
Narendra says
270000 by general rule.
Bhavishya agarwal says
But answer is 300000 Pls help as and is coming 27000
By general rule
So back answer is wrong?
Niharika says
Yes I our book also. I am getting to confused
Yogendra says
Correct answer is 2,70,000 as per Here && GENERAL RULE ]- It says correct rounding off to ‘S *
Anubhav says
5281×3491
5281 is round off to = 5000
3491 is round off to =3500
Estimated product = 5000×3500=17500000
But how???
Sony joy says
5281 …… the numbers 5 and greater 5 round off to next number here 1 is last so 1 is less than 5 so we decrease it to 0 so we get 80 then look up to 8 8 is higher than 5 so we round it up to 10 so it become 300 so 5300 then look 3 less than 5 round it to 0 sooo 5000 will get…… never round the first number example here 1st number is 5 we did nt touch it like that way
3491 one exception 1 become 0
9 become 10
So 4 become 5
Here 5 is the bridge of 0 and 10
3500 is now we got we don’t n know to decrease it or to increase sooo put it like that way if in place of 5 we get 6 we round it as 4000 … or place of 5 it comes 4 we round it as 3000
Sunitha B says
Very nice explanation. Thank you
ShouryaSingh says
9250 ×29
9000×30
9300×30
Anshpreet kaur Mann says
Ask to mam or sir I too have this doubt
Prajwal Dodwad says
In the second problem why you estimate 3491 to 3500. In this number the greatest place is thousand so we should estimate as 3000 na?
Jashan says
We need to give close estimate. 3500 is closer to 3491 but not 3000. You can have multiple appropriate answers for this question but closer answer would be best.
Kannu arora says
The product which is nearest to actual product .that will be actual estimated product.
Priyokumar says
The question is not nearest to actual product. It is about general rule
John says
Why 5291 is rounded to nearest 1000 and 3491 to nearest 100? While the place value of both 5 and 3 are thousands
Cutey pie🦄 says
Why is 5281 multiplied by 1000 and 3491 is multiplied by 100 ? B.T.W, you have used 5281 as 5291 in solution
Priyokumar says
Better to define general rule for estimate elaborately not to make confusion among young learners
Priyokumar says
By observation it comes to my mind about the general rule for estimate. Just consider the leftmost two digit for round off . If the extreme left digit is greater than the other round off must be done to its place but the other digit is greater than the extreme left digit round off must be done to its place eg5291 is rounded off to 5000 whereas 3491 is rounded off to3500 as 5>2 and 3<4.
Aljo says
My also 3,00,000 is the answer in the ncrt book what will l do
Anshul says
It’s wrong in the book
Raghav Upadhyay says
The process which he or she at is raight . I ma a principal of chamile Devi public school 😀😀😀😃😄☺️🥰☺️🙂🙃🙃😉☺️😘🙂🙃😘☺️😁😆😁😃😁😆😄😃😁😁😚😁😁😁😁😁😁😁😁😁😁😆😅😃☺️😄🙄🙄🙄🙄🙄😏😒😟😟😟🥺🥺😬😬😯😬🥺😟😛😊😉😉
Chudamani Sahu says
Estimate the following products using general rule :
a) 1291× 592
Sol : 1291 = 1300
592 = 600
= 1291 × 592 = 1300 × 600
= 780000
b) 9250 × 29
Sol : 9250 = 9250
29 = 30
9250 × 29 = 9250 × 30
= 277500
Swara Dhumal says
In example (b) 5281 is rounded off to nearest thousand and 3491 is rounded off to nearest hundred, why?
Why 3491 is also not rounded off to nearest thousand ?
Hetanshi says
Nice
Diya says
Super
Mounika says
Very is shortcut answer thank you😉😉😉😉😉😉😉😉😉😊😊😊😊😊😊😊😊😊😊😊😎😎😎😎😎😎😎😎😎😎🙄🙄🙄🙄🙄🙄🙄🙄🙄🙄🤗🤗🤗🤗😐🤗🤗🤗🤗
Alka Madaan says
It is very confusing because general rule is not applied. Please explain how you got the answers.
Ridham says
Thanks for this