Answer:
66
Step-by-step explanation:
Use the formula for the mean of a set of numbers:
sum of the numbers
average = --------------------------------
count of numbers
Here we know that the average mark was 68, so we can write:
75 + 62 + 84 + 53 + x
average = 68 = ----------------------------------
5
or 274 + x
68 = -------------------
5
Solving for x, we multiply both sides by 5: 340 = 274 + x.
Subtracting 274 from both sides effectively isolates x:
340 = 274 + x
- 274 -274
------------------------
66 = x
The fifth student's mark was 66.
Answer:3 9/20
Step-by-step explanation:
Answer: 5:4
Step-by-step explanation: you divide them i believe :)
Answer:
14
Step-by-step explanation:
We are given with two
numbers whose first
are same.
It is given that their sum is 
adding the last two corresponding digits gives,

Now adding the rest,
to get 
should not give anything to carry as that will make A in decimal to satisfy the addition.
Therefore,

Thus 
And finally,

Thus 
Now simplifying

Thus
is the answer.
Answser:
It's the first one
Step-by-step explanation: