4 people = 480 grams of pasta
1 person = 480 ÷ 4 = 120 grams of pasta
14 people = 120 x 14 = 1680 grams of pasta
1680g = 1680 ÷ 1000 = 1.68 kg
Answer: 1.68 kg of pasta
-7x+y=42
y=42+7x
5x+13y=66
Substitute for y (meaning put 42+7x into the equation above instead of y because they are equal - see second line of my answer above)
5x+13[42+7x] = 66
5x +546 = 66
5x=66-546
5x=-480
x=-480/5
x=-96
4 and 3
The LCM of these two numbers is 12.
Added together, their sum is 7.
Hence, 5+2+3=10 students play exactly two of these sports.
Answer: 10
28 divided by 2, which is 14.