Let's go through each of the practice problems on the page you uploaded:

1. $(2.8 \times 10^4) \times (4 \times 10^5)$

To multiply two numbers in scientific notation, multiply the coefficients and add the exponents: $(2.8 \times 10^4) \times (4 \times 10^5) = (2.8 \times 4) \times 10^{4+5} = 11.2 \times 10^9$ The answer is $1.12 \times 10^{10}$ in scientific notation (adjusting the decimal place).

2. $\frac{6 \times 10^9}{2.4 \times 10^3}$

To divide two numbers in scientific notation, divide the coefficients and subtract the exponents: $\frac{6 \times 10^9}{2.4 \times 10^3} = \frac{6}{2.4} \times 10^{9-3} = 2.5 \times 10^6$ The answer is $2.5 \times 10^6$.

3. $(4.1 \times 10^4) + (5.6 \times 10^6)$

To add or subtract numbers in scientific notation, first express both numbers with the same exponent: $4.1 \times 10^4 = 0.041 \times 10^6$ Now add them: $(0.041 \times 10^6) + (5.6 \times 10^6) = (0.041 + 5.6) \times 10^6 = 5.641 \times 10^6$ The answer is $5.641 \times 10^6$.

4. Town A and Town B population comparison:

• Population of Town A: $1.26 \times 10^5$
• Population of Town B: $2.8 \times 10^4$

To find how many times greater Town A's population is than Town B: $\frac{1.26 \times 10^5}{2.8 \times 10^4} = \frac{1.26}{2.8} \times 10^{5-4} = 0.45 \times 10^1 = 4.5$ So, the population of Town A is 4.5 times greater than Town B.

Would you like more details on any of these solutions, or do you have further questions?

Here are five related questions for practice:

1. How do you subtract two numbers in scientific notation?
2. What happens when you divide numbers with the same exponent but different coefficients?
3. Why is adjusting the coefficient in scientific notation necessary when adding?
4. How do you convert a large number, like 12,000, into scientific notation?
5. What is the rule for multiplying numbers with different powers of ten?

Tip: Always make sure to adjust the decimal so that the coefficient in scientific notation is between 1 and 10.