Call (F) the age of the father and (J) the age of Julio
The F & J are related in this way: F=4J
Now you have a restriction in the form of inequality: The sum of both ages has to be greater or equal than 55.
Algebraically that is: F + J ≥ 55
You can substitute F with 4J to find the solution for J:
4J + J ≥ 55
5J ≥ 55
Now divide both sides by 5
5J/5 ≥ 55/5
J ≥ 11
That Imposes a lower boundary for the value of J of 11, meaning that the youngest age of Julio can be 11
Dimensional Analysis is the way you want to go

Answer:
Step-by-step explanation:
Susan started her homework at = 1:59 pm
She took time = 96 mins
Time at which she had volleyball practice = 4:00 pm
So, time between her starting of homework and starting of volleyball is given by
1:59 pm to 4:00 pm = 2 hrs and 1 mins
2 hr 1 min = 120 mins + 1 min = 121 mins
But she took 96 mins to do her homework, so
Out of 121 mins, 96 mins she took for homework
Remaining time = 121 mins - 96 mins = 25 mins
Therefore, time Susan had between finishing her homework and the beginning of volleyball practice is 25 mins
Option I
(3x+4)cm =(2x+10)cm
3x-2x=6
x=6
Option II
(3x+4)= (x+12)
3x-x=12-4
2x=8
x=4
Option III
(2x+10)= (x+12)
2x-x=12-10
x=2