Answer:
- 1/2
Step-by-step explanation:
turn 2/5 to have the same denominator as 10
2 ( 2 ) = 4
5 ( 2 ) = 10
4/10 - 9/10
= -5/10
simplify
-5/10 = -1/2
hope this helps
Answer:
(A) 509.78
We need to move the decimal point after the first non-zero digit
So,
=> 5.0978 × 10² (Since the decimal point is moved two places to the left)
(B) 0.0289
Again after the first non-zero digit:
So, it becomes:
=> 2.89 × 10⁻² (Since the decimal point is moved 2 places to the right so it will be negative also)
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.
Gain - loss = profit
55- 45 = $10 net profit