Relative frequency is the absolute frequency (i.e. the number of times of the wanted result) divided by the total number of events.
In this case you have to calculate: the number of heads that came up divided by the number of times the coin was flipped.
Number of times the coin was flipped: 20
Numbef of times head came up: 7
Relative frequency: 7 / 20 = 0.35, which is the option B.
Answer:

Step-by-step explanation:
Given

Required
Simpify
The very first step is to take LCM of the given expression

Perform arithmetic operations o the numerator

Divide the numerator and denominator by 2


The expression can't be further simplified;
Hence,
= 
Answer:
j(x) = [ (3/10) cookie/student ]x
Step-by-step explanation:
The "unit rate" here is
3 jumbo cookies
------------------------- = (3/10) cookie/student
10 students
Then the number of cookies needed to feed x students is
j(x) = [ (3/10) cookie/student ]x