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# Best way to convert large fractions to decimals

E.g. I got stuck on how to do 11/275 during a case

What is the best trick for something like this and many others

Are there any recourses to practice large fractions?

E.g. I got stuck on how to do 11/275 during a case

What is the best trick for something like this and many others

Are there any recourses to practice large fractions?

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Hi Anonymous,

assuming you can approximate numbers, in this case you can find what is a relatively small percentage (eg 1%) and see how the number you have to calculate compares to that.

In this case, 1% of 275 is 2.75, which means 2% is 5.5. At this stage, you would probably notice that 11 is therefore exactly 4%.

Best,

Francesco

Hi Anonymous,

assuming you can approximate numbers, in this case you can find what is a relatively small percentage (eg 1%) and see how the number you have to calculate compares to that.

In this case, 1% of 275 is 2.75, which means 2% is 5.5. At this stage, you would probably notice that 11 is therefore exactly 4%.

Best,

Francesco

Using percetage may be an easy way to covert complex fractions into decimals.

eg. 11/275

275 = 200 + 75

taking 4% of (200 + 75) = 8 + 3 = 11 thus 11/275 = 4% = 0.04

Other way round if you can image breaking the bigger number

11/275 = 11/5 *1/5*1/11 = 1/25 = 4%

There is no hardcoded rule you may use which ever approach comes to your mind and you seem comfortable with it. Hope this is helpful.

Using percetage may be an easy way to covert complex fractions into decimals.

eg. 11/275

275 = 200 + 75

taking 4% of (200 + 75) = 8 + 3 = 11 thus 11/275 = 4% = 0.04

Other way round if you can image breaking the bigger number

11/275 = 11/5 *1/5*1/11 = 1/25 = 4%

There is no hardcoded rule you may use which ever approach comes to your mind and you seem comfortable with it. Hope this is helpful.

Hi,
here you can find a detailed approach to solve it in a quick approximated way and in an accurate way: https://www.youtube.com/watch?v=do_IbHId2Os

I recommend you to take a look at the channel, I really appreciate their video on fast math.

Best,
Antonello

Hi,
here you can find a detailed approach to solve it in a quick approximated way and in an accurate way: https://www.youtube.com/watch?v=do_IbHId2Os

I recommend you to take a look at the channel, I really appreciate their video on fast math.

Best,
Antonello

Hi,

You should approximate it:

50% of 275 = 135

110 is roughly 40%, thus 11 is 4%

Best

Hi,

You should approximate it:

50% of 275 = 135

110 is roughly 40%, thus 11 is 4%

Best

I typically convert the denominator to 100, so in this case for simplicity I would divide denominator by 3, giving me approximately 3.67%. Then I would round up or down depending on whether I have overestimated or underestimated based on the earlier division, so in this case I would round up and say about 3.9%-4%.

But you should ask if rough estimations are fine. 90% of the time your interviewer will be ok with rounding.

I typically convert the denominator to 100, so in this case for simplicity I would divide denominator by 3, giving me approximately 3.67%. Then I would round up or down depending on whether I have overestimated or underestimated based on the earlier division, so in this case I would round up and say about 3.9%-4%.

But you should ask if rough estimations are fine. 90% of the time your interviewer will be ok with rounding.

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