Answer:
a = 20
Step-by-step explanation:
The mean is calculated as
mean =
= =
Then
= 27 ( multiply both sides by 5 to clear the fraction )
115 + a = 135 ( subtract 115 from both sides )
a = 20
Is it A or C And I need a explanation Please I already found slope ,
1 answer:
You might be interested in
Let 
be the amount of time it takes to perform an arm routine and 
be the amount of time it takes to perform an abdominal routine. We see:
Subtracting the second equation from the first gives
. Substituting gives 
, so 
and 
.
Thus, an arm routine takes ten minutes and an abdominal routine takes thirty minutes.
Subtracting the second equation from the first gives
Thus, an arm routine takes ten minutes and an abdominal routine takes thirty minutes.