This is a true statement.
Consider two events A and B. We say they are complementary if P(A)+P(B) = 1
This means that either event A or event B must happen, since the "1" represents 100% probability. Having a probability of 100% means absolute certainty.
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Example:
A = the event it rains
B = the event it does not rain
P(A) = 0.30 = 30% chance of rain
P(B) = 0.70 = 70% chance it does not rain
P(A)+P(B) = 0.30+0.70 = 1
So this shows the two events are complementary.
1. 2x+3=4x+2
⇒ 4x-2x=3-2
2x=1
x=1/2
There is one solution.
2. 18p-10p=5+6/2
8p=5+3
8p=8
p=8:8
p=1
3. 6a/3=2a
2a-a= -2 -3
a= - 5
4. 5+r-2=9,
5-2+r=9
3+r=9
r=9 - 3
r=6
5. -0,9 m= 9
m= - 10
6. -2 (x+1/4)=5-1=4
x+1/4= -2
x= -2 - 1/4
x= -8/4 - 1/4= - 9/4
7. 6f+4f= 6 + 12
10 f = 18
f=18/10=1,8
8. 7n - 3n= 16
4n=16
n=16:4
n=4
9. 1/3m-5/6m= - 15 - 3
2/6 m-5/6=-18
- 3/6m=-18 ⇒ 1/2m=18
m=2*18=36
Well let's see.
The equation has exactly one solution.
Hope this helps.
We have been given that a store manager paid $95 for an item and set the selling price at $116.85. We are asked to find the percent mark-up.
We will use percent increase formula to solve our given problem.
Therefore, the mark-up will be 23% and option 'b' is the correct choice.
