Answer:
first you subtract 5 from both sides
your left with 3x=11
divide by 3 on both sides
x=3.666 repeating
Step-by-step explanation:
A and b can do a piece of work in 12 days. If a alone have to finish the job among b and c so
A and b=12
A (24 days alone without b)
So if b and c 15 days and c 20 days. If a have to do all I would add 24 and 15 and 20 which would be 59 days
The mean is the average of the numbers.
It is easy to calculate: add up all the numbers, then divide by how many numbers there are.
Let the number of sit-ups you have to do Sunday be x. Then the sum of all sit-ups is
100+65+120+150+90+0+x=525+x.
The number of days is 7.
Thus, the mean is
You know that the mean number of sit-ups per day is 100, equate these two means and solve the equation:
Answer: 175 sit-ups