Show work. Express answers in scientific notation. May round to one decimal place as in 3.2×10^5.
1. (4×10^7) × (2×10^8)
2. (3.2×10^5) × (2×10^4)
3. (4×10^3) + (5×10^2)
4. (9×10^13) ÷ (3×10^10)
Compare the #s in each pair and give the factor by which the #s differ. Example: 10^6 is 10^2, or 100, timea as large as 10^4.
1) 250 million, 5 billion
2) 9.3 x 10^2 and 3.1 x 10^-2
3) 10^-8 and 2 × 10^-13
+37097 I'll show you how to do the first one
1) 4 x 10^7 x 2x10^8 = (4x2) x 10^(7+8) = 8 x 10^15
Do you see?
250 million and 5 billion
250 million = 250 000 000 = 2.5 x 10^8 5 billion = 5 000 000 000 = 5 x 10^9
10^8 and 10^9 differ by 10^1 = a factor of 10
(though it is actually 20... but I am not sure that was what was asked...I think they just wanted you to compare the 10 exponents)
5000000000/250000000 = 20
