the question in English
Juan has blue cubes with a 55 mm edge and red cubes with a 45 mm edge. He stacks them in two columns, one of each color; he wants the two columns to be the same height. How many cubes does he need, as a minimum, of each color?
Let
x---------> the number of blue cubes
y--------> the number of red cubes
we know that
Juan wants that the two columns to be the same height
so

solve for y

I proceed to calculate a table, assuming values of x to calculate the value of y. When the values of x and y are whole numbers, I will have found the solution.
the table in the attached figure
therefore
<u>the answer is</u>
9 blue cubes
11 red cubes
Answer:
C. 1.15<em>x</em> because adding 15% to the cost of the haircut is the same as multiplying the cost by 1.15.
Step-by-step explanation:
This answer is correct because, adding 0.15x (or 15%) to the total amount is the same as multiplying the cost by 1.15. This is because, the 1 that is added to 0.15 represents the total, since we are just multiplying instead of adding to it.
Hope this helps! :D