Hi Agata,

Great question!

1. Cross out 0s
   1. ​10,000/18
2. Simplify
   1. 5,000/9 (cut in half)
3. If rounding, get to closest, and add a segment
   1. 5,000/10 = 500
   2. It's a bit less (1/10), so add another 50
   3. = approx 550
4. If you're not allowed to round, long division

What's that you say? I may have to learn long division and long multiplication? Yes. 100% :)

Personnally, I always go to things i know well. For instance here, 1 millions is half of 2 millions so you could go with two millions divided by 1800 and take half of your result.

Another way is to realize that 1800 is only 10% smaller than 2000. 1800= 90% *2000=90/100*2000.

So 1 000 000/1800 is actually 100/90* 1 000 000/2000=100/90*500.

Then it's easy because 100/90=10/9=1.11.
So 1 000 000/1800= 1.11*500=555.

Here i detailed all step but this can be done much easier once you realized that you can use 2000 and go from that.

Here is the detailled version for both calculation

(edited)

Hello!

I would divide into 2000 instead. Then remove zeros, and simple division.

Once it´s done, make it ~20% higher for the simplificaiton we made.

Best,

Clara

Hi Agata,

There are plenty of threads and tons of tips and prep guidance for maths. Please search the forum. Have a look at these:

• https://www.preplounge.com/en/consulting-forum/moltiplicationsdivisions-with-6-digits-numbers-estimation-math_tricks-2925
• https://www.preplounge.com/en/consulting-forum/best-apps-for-mental-maths-4376
• https://www.preplounge.com/en/consulting-forum/case-math-practice-6877