for questions 15 and 16, multiply. write in scientific notation
(9x10^4)(8x10^6)
7.2x10^25
1.7x10^11
7.2x10^11
1.7x10^25
(1.7x10^-4)(5x10^-5)
8.5x10^-9
8.5x10^20
6.7x10^-9
6.7x10^20
for 15 I'm thinking it is c and 16 could be A
pls check my work and explain what i did wrong
right on both of them.
For question 15, you have (9x10^4)(8x10^6). To multiply these numbers in scientific notation, you need to multiply the two coefficients (9 and 8) and then add the exponents of the same base (10^4 and 10^6).
9 x 8 = 72
10^4 x 10^6 = 10^(4+6) = 10^10
Therefore, the result is 72x10^10 in scientific notation.
Now, let's compare the options:
a) 7.2x10^25
b) 1.7x10^11
c) 7.2x10^11
d) 1.7x10^25
From the calculation we did, the result is 72x10^10, and this option is not listed. Therefore, none of the options is correct. The correct answer should be 72x10^10.
For question 16, you have (1.7x10^-4)(5x10^-5). Similarly, you need to multiply the coefficients (1.7 and 5) and add the exponents of the same base (-4 and -5).
1.7 x 5 = 8.5
10^-4 x 10^-5 = 10^(-4-5) = 10^-9
Therefore, the result is 8.5x10^-9 in scientific notation.
Now, let's compare the options:
a) 8.5x10^-9
b) 8.5x10^20
c) 6.7x10^-9
d) 6.7x10^20
From the calculation we did, the result is 8.5x10^-9, and this option is listed as the first option (a). So, your answer for question 16 is correct.
To summarize:
15 - None of the options is correct. The correct answer is 72x10^10.
16 - The correct answer is a) 8.5x10^-9.