Choosing "r" things from a set of "n" can be done in this many ways:
combinations = n! / [r! * (n-r)!]
combinations = 7! / [3! * 4!]
combinations = 7 * 6 * 5 / 6
combinations = 35
Source:http://www.1728.org/combinat.htm
This is just a vertical line...
5x+6=26
5x=20
x=4
Answer: 
Step-by-step explanation:
Given
Mark up price is 25% higher than cost price
The shopkeeper gives a discount of 10%
Suppose the cost price is 
Mark up price is 
Selling price is

It is given Rs150

Marked up price is 
Ommon multiples of 4<span> & </span>7<span> I wonder what are the numbers that are </span>common multiples of 4 and 7<span>. I used the </span>4<span>first - </span>4<span>,8,12,16, etc. - and the </span>7<span> is </span>7<span>,21,28, etc hope this is what you need .
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