Use the difference of 2 squares (a - b)(a + b) = a^2 - b^2:-
(x - 1/x)(x + 1/x) = x^2 - (1/x)^2
= x^2 - 1/x^2
(x ^2 - 1/x^2)(x^2 + 1 /x^2)
= x^4 - 1/x^4
(x^4 - 1/x^4)(x^4 + 1/x^4)
= x^8 - 1 /x^8 Answer
In case A, as the error would be a difference of 1, the assumption could be mantained, but in case B the difference will be bigger, showing that the ratio is not 3:1 but 4:1.
<h3><u>Ratios</u></h3>
Given that a preliminary study was carried out to test the hypothesis that the ratio of white to dark herons on the island was 3:1, but A) a small census found 16 white morphs and 4 dark, to determine if the assumption of a 3 :1 ratio could be rejected, and B) to determine the same question if the census were larger with 160 white morphs and 40 dark, the following calculations must be made:
A)
- 3 + 1 = 4
- 16 + 4 = 20
- 4 = 20
- 3 = X
- 60 / 4 = X
- 15 = X
- Therefore, as the error would be a difference of 1, the assumption could be mantained.
B)
- 3 + 1 = 4
- 160 + 40 = 200
- 150 = 3:1
- In this case, the difference will be bigger, showing that the ratio is not 3:1 but 4:1.
Learn more about ratios in brainly.com/question/1504221
Answer: 13%
Step-by-step explanation:
The formula to find the simple interest is given by :-
, where P is the principal amount, r is rate of interest () in decimal and t is the time ( in years).
Given : P = $19,100 , I=$9932.00 and t= 4 years
Substitute all the above values in the formula , we get
In percent , 
Hence, the rate of interest = 13%
Answer: Lucy pays $ 492.58 back altogether.
Step-by-step explanation:
Formula : Interest = Principal x Rate x Time
Given: Principal = $425 , rate = 5.3% = 0.053 , time = 3 years
Interest = 425 x 0.053 x 3 ≈ $ 67.58
Total amount need to pay back = Principal + Interest
= $ (425+67.58)
= $ 492.58
Hence, Lucy pays $ 492.58 back altogether.
