The answer is A) The student failed to properly apply the distributive property.
Cringe to fingernails on a chalkboard
Answer: A. An OPEN circle on the number 5 and an arrow shading to the RIGHT.
Answer:
90 g of water should be added and he will make 900 g of solution.
Step-by-step explanation:
Let x g be the amount of salt Ilya add to 810g of water to make 10% solution. Then 810+x g is the amount of new solution. Thus,
810+x - 100%,
x - 10%.
Mathematically,

So 90 g of water should be added and he will make 810+90=900 g of solution.