since she drank 8 water bottles a day, and you there are 7 days in a week, you have to multiply 7 and 8.
7 * 8 = 56
x = 7, y = 10.5.
y = 2x - 3.5
-2y = -x - 14
multiply the first equation by 2:
2y = 4x - 7
now add this equation to the second one:
0 = 3x - 21
3x = 21
x = 7.
now substitute x = 7 in the first equation to fund the value of y:
y = 2(7) - 3.5
y = 10.5.
7 quarts = 28 cups
10 cups = 2.5 quarts
in order to solve the two different questions in the problem, starting with a ratio of the number of quarts to the number of cups would be :
so, for every 1 quart of milk, she can pour 4 cups. using this ratio, we can set up equivalent ratios, or proportions, to solve for the missing value. for the first question, we need to know that amount of cups in 7 quarts:
we can solve for 'x' by multiplying the numerator and denominator by the same factor, in this case '7'. so, 4 x 7 = 28 cups.
next, we need to solve for the amount of quarts needed for 10 cups:
4 x 2.5 = 10, so we need to multiply the numerator by 2.5: 1 x 2.5 = 2.5 quarts.
multiple the decimal by 100 to convert a decimal to a percent