Let the unknown number be x.
<span>sum of a number and one: x + 1
</span>
<span>sum of a number and one is doubled: 2(x + 1)
</span>
<span>three less than the number: x - 3
2(x + 1) = x - 3
2x + 2 = x - 3
x + 2 = -3
x = -5
The number is -5.
</span>
Answer:
21/18 which simplifies to <u>7/6</u>
Step-by-step explanation:
Answer:
C, 6
Step-by-step explanation:
31-13 is 18, 18/3 is 6.
12/3 = 4
4 cars per hour
4 x 5 = $20
20 x 8 = $160 for 8 hrs
Answer: 547
Step-by-step explanation: The margin of error formulae is given below as
Margin of error = critical value ×(σ/√n)
Where σ = standard deviation and n is the sample size.
From our question, margin of error = 0.08
Variance is 1.691,
hence σ = √variance = √1.691
= 1.3.
We will be using a z test for our critical value this is because a soft drink manufacturer will always produce drinks more than 30 in numbers.
The critical value for a 85% confidence interval is 1.44.
Hence critical value is 1.44.
By substituting the parameters, we have that
0.08 = 1.44 × 1.3/ √n
0.08 = 1.873/ √n
By cross multiplying
0.08 × √n = 1.873
√n = 1.873/ 0.08
√n = 23.41
n = (23.41)²
n = 547.