Answer:
26) x = 4
Step-by-step explanation:
26)
20x + 5 + 24x - 1 = 180
20x + 24x = 180 + 1 - 5
44x = 176
x = 176/44
x = 4
6x would be 6 x ? + 2 x ? = 12 probably 6 x 1 + 2 x 3 = 12 same thing for the second one.
Answer:
B and D
Step-by-step explanation:
look at the decimal point and 6 over 100 is 6%of 100
30 because 1/5th of an hour is 12 min, 60 divided by 12 is 5, 6 times 5 is 30
Answer: the company should promote 4412 hours for these bulbs.
Step-by-step explanation:
Assuming that the lives of the bulbs are normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - µ)/σ
Where
x = lifetime of the bulbs in hours.
µ = mean hours
σ = standard deviation
From the information given,
µ = 4000 hours
σ = 200 hours
If only 2% burn out, then the company would promote 98% would meet the claimed lifetime. Looking at the normal distribution table, the z score corresponding to a probability of 0.98 is 2.06. Therefore,
2.06 = (x - 4000)/200
Cross multiplying, it becomes
200 × 2.06 = (x - 4000)
412 = x - 4000
x = 4000 + 412
x = 4412 hours
