You will need

- pen, paper, analytical thinking

Instruction

1

Write the problem statement. 40% vinegar is 100%, you need to find how much to take of vinegar to obtain a 6% vinegar. It will be H. Recorded two par: 40%=100%, 6%=H.

2

3

Get vinegar essence is 15% of the total water and acetic solution.

It is possible to take 15 ml of vinegar and 75 ml of water to obtain approximately 100 ml of 6% vinegar. About - because water has the property of substitution, and withdrawal of different solutions may yield slightly less than originally planned.

It is possible to take 15 ml of vinegar and 75 ml of water to obtain approximately 100 ml of 6% vinegar. About - because water has the property of substitution, and withdrawal of different solutions may yield slightly less than originally planned.

4

The task is more difficult. Is buckwheat flour with a protein content of 12.6 g per 100 g of dry product. And there is a starch with a protein content of 1 g per 100 g of dry product. You need to make the starch-flour mixture with a protein content of 2 g per 100 g of dry product.

5

Take for x the starch content in the mixture in grams, (100-x) content of buckwheat flour in the mixture in grams.

6

Then 1*x/100 - how many grams of protein is necessary for starch 12,6*(100-x)/100 - how many grams of protein accounts for buckwheat flour.

The sum of these fractions is 2 g of protein per 100 g of the mixture.

The sum of these fractions is 2 g of protein per 100 g of the mixture.

7

After solving the equation, we find that to obtain a mixture with a content of 2 g of protein we need to take 91 g starch and 9 g of buckwheat flour.