Answer:
B = 43
Step-by-step explanation:
Susanne will be x because both people use her as a comparsion. Bob's expression would be 4x, and Dakota's expression would be x - 3. If Dakota's and Bob's age sum is 93 then form the equation 4x + x - 3 = 93 to find Susanne's age. I'll do the steps below.
4x + x - 3 = 93
5x - 3 = 93
5x = 96
x = 19.2
Answer:
Grace should use her phone for 58 minutes to maintain an average of 55 minutes.
Step-by-step explanation:
Usage of first month = 43 minutes
Second month = 62 minutes
Third Minutes = 57 minutes
Let, the usage of fourth month = k minutes
Mean of the data = 5 minutes
Now, Average of a Data = 
⇒
or, 55 x 4 = 162 + k
⇒ 220 - 162 = k
or, k = 58 minutes
So, Grace should use her phone for 58 minutes to maintain an average of 55 minutes.
Option B gives the correct answer.The step by step solution using the FOIL method of multiplication is given below: