Assuming 5a3 equals 5a^3, and the same for everything else, you would plug in 4 for a, so 5(4)^3 - 2(4)^2 + 4 - 45, which equals 247.
Answer:
The bulbs should be replaced each 1436.9 hours.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

How often should the bulbs be replaced so that no more than 1% burn out between replacement periods?
This is the first percentile of hours. So it is X when Z has a pvalue of 0.01.
So it is X when Z = -2.33.




The bulbs should be replaced each 1436.9 hours.
The above question is asking us to check if the exponents are written in the correct way or not.Let us look at the options one by one.
1) The exponent denotes the number of time the letter or number is multiplied.We have six x which are multiplied so the exponent for x which is 6 is right .The exponent is written correct .
2)We have seven A which are multiplied and five B multiplied making the exponent of A as 7 and B as 5 .The exponents are written correct.
3)There are six b and six c .The exponent rule has been followed here that is we can keep bc inside parenthesis and make 6 as the exponent.
4)Here exponent for x,y,z all are 5. we can not remove the exponent of x and y .It is not following the exponent rule .
Option 4 is not true.
Answer:
B. 13
Explanation:

Logarithm rules:

Breakdown of the expression:



insert given values


2*3 = 6 teaspoons per day per child
6*5 = 30 teaspoons
30*3 = 90 teaspoons
You need 90 teaspoons
1 teaspoon = 4.9289 mL
90*4.9289 = 443.6010 mL
443.6010 / 150 = 2.9573 bottles
You need at least 3 bottles