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:
axis of symetry
Step-by-step explanation:
Beast_Building on yt
Answer:
6
Step-by-step explanation:
1. get rid of parentheses: 12x -6 = 10x +6
2. group like terns together: 12x-10x = 6+6
3. simplify: 2x = 12
4. divide both sides by 2: x=6
It sounds like initially we have a total of 18*5 = 90. Then we are adding 5 + 4 +3 +2 +1 to this.
so that gives us 105.
105/5 = 21
Answer:

General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra I</u>
Step-by-step explanation:
<u>Step 1: Define</u>
<em>Identify</em>
<em />
<em />
<em />
<u>Step 2: Simplify</u>
- Combine like terms (x):

- Combine like terms (y):
