Can someone help me with quick maths?

[feellikelilac]

If 16% of a number is 12000 and 6400

Then what would 18% be of the same figures?

So 16% of N is 12,000?

18% of N is 12,000 x 18/16 = 13,500

You can work it out by multiplying both figures by 18/16. That gives 13500 and 7200

13,500 & 7,200

Are you asking for a specific reason? Do you need to understand the technique?

Divide the figure by 16 to find 1%.
Then multiply to find what you want, eg x 18.

If you want to do this sum in your head, halve it to get 8%, halve it again to get 4%, halve again to find 2%. Once you know what 2% is, add that figure to the 16% and you have 18%.

Divide both answers by 16 to get 1% then multiply by 18 to get 18%. Or multiply by 18 and divide by 16, it's the same thing.

Yes, just take it back to 1% and then multiply by whatever alternative percentage you need.

If 16% of a number is 12000 then the original number is 12000/16*100 = 75,000 (divide it by 16 to get 1% then multiply by 100 to get 100%).

If 16% of a different number is 6400 then the original number here is 6400/16*100 = 40,000

18% of 75,000 is 75000 * 0.18 = 13,500
18% of 40,000 is 40,000 * 0.18 = 7200