Answer:
b = 1
Step-by-step explanation:
Given the equation is:
- 5b + 2b - (-b) + 7 = 5
We separate the terms of b and the constants. To do that we subtract 7 from both the sides. We get:
- 5b + 2b - (-b) + 7 - 7 = 5 - 7
⇒ - 5b + 2b - (-b) = - 2
Now, simplifying the terms with 'b'.
⇒ -5b + 2b + b = - 2
⇒ (-5 + 2 + 1)b = - 2
⇒ -2b = -2
Dividing both the sides by -2, we get:
b = 1 which is the required answer.
If a 12 oz bottle of shampoo lasted for 16 weeks, we have a ratio of 12:16 which can be shortened to 3:4.
Now if we have 18 oz bottle we know that it's 1/2 more than 12 oz bottle, so the ratio will be also 1/2 more. So if it was 12:16, the new ratio will be:
12 + (1/2 * 12) : 16 + (1/2 * 16)
12 + 6 : 16 + 8
18 : 24
It means that 18 oz bottle should last for 24 weeks. Of course the ratio has to stay the same in its lowest form in both situations and as 18:24 can be shortened to 3:4, it proves it's correct :)
Answer:
-33 and -21
Step-by-step explanation:
-36, <u>-33</u>, -30, -27, -24, <u>-21</u>, -18
-36
-36 + 3 = -33
-33 + 3 = -30
-30 + 3 = -27
-27 + 3 = -24
-24 + 3 = -21
-21 + 3 = -18
Answer:
n = 61 costumers
Step-by-step explanation:
For calculating the number of costumers he should sample we use the next equation:
Where E is the error that we are prepared to accept, in this case E = 0.15
How we don't know the value of p, we can estimate it like p = 0.5
∝ = 1-0.98 = 0.02
1-∝/2 = 0.99
n = 60.32 costumers
n ≈ 61 costumers
Answer:
- Walnuts cost $1.75, chocolate chips cost $2.75
Step-by-step explanation:
<h3>Let the costs be:</h3>
- Walnuts - x
- Chocolate chips - y
<h3>Set equations as per question</h3>
For 7 pounds of walnuts and 9 pounds of chocolate chips, the total cost is $37:
For 5 pounds of walnuts and 3 pounds of chocolate chips, the total cost is $17:
<h3>Solve the system by elimination</h3>
Multiply the second equation by 3 and subtract the first equation, solve for x:
- 3(5x + 3y) - (7x + 9y) = 3(17) - 37
- 15x + 9y - 7x - 9y = 51 - 37
- 8x = 14
- x = 14/8
- x = 1.75
Find the value of y:
- 7*1.75 + 9y = 37
- 12.25 + 9y = 37
- 9y = 37 - 12.25
- 9y = 24.75
- y = 24.75/9
- y = 2.75