-2/5 + 5/6
To add these fractions, you need to find a common denominator. The least common multiple of 5 and 6 is 30.
Converting -2/5 to have a denominator of 30:
Multiply the numerator and denominator by 6:
(-2/5) * (6/6) = -12/30
Converting 5/6 to have a denominator of 30:
Multiply the numerator and denominator by 5:
(5/6) * (5/5) = 25/30
Now, you can add the fractions:
-12/30 + 25/30 = (25 - 12) / 30 = 13/30
So, -2/5 + 5/6 = 13/30.
28 = 4/7y
To solve the equation 28 = 4/7y, you need to isolate the variable y on one side of the equation.
First, multiply both sides of the equation by 7 to eliminate the fraction:
7 * 28 = (4/7y) * 7
196 = 4y
Next, divide both sides of the equation by 4 to solve for y:
196/4 = 4y/4
49 = y
Therefore, the solution to the equation 28 = 4/7y is y = 49.
3u = 15/4
To solve the equation 3u = 15/4, you need to isolate the variable u on one side of the equation.
First, divide both sides of the equation by 3 to get u by itself:
(3u)/3 = (15/4)/3
u = 15/4 * (1/3)
To simplify the right side of the equation, multiply the numerators and the denominators:
u = (15 * 1) / (4 * 3)
u = 15/12
Next, simplify the fraction by finding the greatest common divisor of 15 and 12, which is 3:
u = (15/3) / (12/3)
u = 5/4
Therefore, the solution to the equation 3u = 15/4 is u = 5/4.
4x/5 = 20
To solve the equation (4x/5) = 20, you need to isolate the variable x on one side of the equation.
To eliminate the fraction, multiply both sides of the equation by 5:
5 * (4x/5) = 20 * 5
(5/1) * (4x/5) = 100
(5 * 4x) / 5 = 100
4x = 100
Now, divide both sides of the equation by 4 to solve for x:
(4x)/4 = 100/4
x = 25
Therefore, the solution to the equation (4x/5) = 20 is x = 25.