Step-by-step explanation:
Multiplication of fractions is easiest operation. Simply multiple numerator to numerator and denominator to denominator. For example,

Addition and subtraction requires that we find a common demoninator.
For example,

The common denominator is 12. So I need to muliply each fraction to get the right denominator. 4*3 = 12.

Then we add the numerators

Then we should reduce.

Division is a little trickier because we have to flip-flop the second term and then multiply. For example: 
Answer:
Step-by-step explanation:
3y + 1 - 2y = -3 -3y
4y = -4
y = -1
We have to calculate the 20% of $30.75
The 20% of $30.75=(20/100)*$30.75=(20*$30.75)/100=$6.15
The sale price of the jacket was $6.15.
Answer:
25/9
Step-by-step explanation:
25/9