# Thread: need help explaining a maths problem

1. ## need help explaining a maths problem

hello , this is my problem : calculate (22*28*34*40)/(11*14*17*20) without using a calculator , i cant calculated without a calculator but with a calculator i get 16 ( google calculator) but how do i do this in my mind and relativly fast? is there a trick of some sort? thank you for your time.

2. There is no special trick. Just by looking and by cancellation only. Notice that 22/11 = 2
28/14 = 2
34/17 = 2
40/20 = 2
And then, 2*2*2*2 = 16.

3. Hello, NiceBoy92!

Calculate: .$\displaystyle \frac{22\cdot28\cdot34\cdot40}{11\cdot14\cdot17\cd ot20}$ .without using a calculator.
You never taught how to reduce fractions?

As ticbol pointed out, we have: .$\displaystyle \frac{22}{11}\cdot\frac{28}{14}\cdot\frac{34}{17}\ cdot\frac{40}{20}$

Got it?

4. ## hi

hi every one this is my 1st time in this forum , i hope it can help me with any quetions))

5. Originally Posted by BORZ
hi every one this is my 1st time in this forum , i hope it can help me with any quetions))
Post a question and we will do our best to help you.