First off, the underline underneath means plus or minus, since when you take the square root of something, the answer can be negative or positive at the same time
1. 64 is a perfect square. 8 x 8 = 64, therefore it is +- (plus or minus) 8.
2. 45 is not a perfect square, so you can pull out numbers or plug into a calculator and estimate.
Both answers: Since 45 is divisible by 9 and five, you can break a nine into two threes, therefore pull it out, and since the answer is negative, you get:
-3(5)^0.5 (an exponent of one-half or 0.5 means square root)
If you solve by calculator, the answer is ~= (approximately equal to) -6.72
3. Since 90 is not a perfect square, repeat the previous question. 9 can go into 90, therefore you can pull out two threes and are left with: +-3(10)^0.5
Using the calculator, you get ~= +-9.49
Answer:
12
Step-by-step explanation:
I think you have to use the product rule for counting- which is where you multiply the two numbers. I'm not sure if this is right but I hope I helped
Answer:
0.66608
Step-by-step explanation:
Equipment = 3 fans
Mortality = 0.098
We are required to find probability that equipment gets to work for 5years
The question says forces of mortality is constant and also equal to 0.098
To calculate p(x>5)
We will do this by calculating exponentially
e^-0.098x5
= 0.612626394
Probability that at least 2 fans out of 3 are working
3(0.612626394)²+(1-0.612626394)+(0.612626394)³
= 1.1259333x0.3873736+0.2299255
= 0.6660823470
This is approximately
<u>0.6608</u>
this is the probability that the equipment will work for at least 5years
Answer: L = 29cm
Step-by-step explanation:
Let's go!!
To find any rectangle area, you have to apply this formula: A = L . w , where L is the length and w is the width.
So, we have w = L - 13 (the width is 13 less than the Length) and then, perimeter is 90 cm.
Well, I hope you remember that the perimeter of rectangle is 2L + 2W. In this case, 2L + 2w = 90
Then, you might to solve this system of equation:
2L + 2w = 90
w = L - 13
Simplifying the first equation, you'll have L + w = 45 (you can divide everything of 2).
Our new system:
L + w = 45
w = L - 13
Using the substituition method:
L + L - 13 = 45
2L = 58
L = 29 cm
the width is 29 - 13 = 16 cm
