a half-life of uranium-235 is 700,000,000 years. The half-life of uranium-238 is 4.463x10^11 years longer. What is the half-life of uranium-238? The answer should be in decimal form.

Question

a. 516,300,000,000
b. 447,000,000,000
c. 11,463,000,000

Answer 1

To find the half-life of uranium-238, we can subtract the given difference in half-lives from the half-life of uranium-235.

The given difference in half-lives is 4.463x10^11 years longer.

So, the half-life of uranium-238 is 700,000,000 years + 4.463x10^11 years.

To write this in decimal form, we can evaluate the expression:

700,000,000 + 4.463x10^11 = 700,000,000 + 446,300,000,000 = 447,000,000,000.

Therefore, the half-life of uranium-238 is 447,000,000,000 years.

The correct answer is b. 447,000,000,000.

Answer 2

A mobile phone holds 1.28x10^11 bytes of storage. You can also pay more money to get an additional 384,000,000,000 bytes, How much storage would your phone have if you buy the additional bytes? The answer should be in scientific notation.

Answer 3

To calculate the total storage of the phone if you buy the additional bytes, we need to add the two storage values:

1.28x10^11 bytes + 384,000,000,000 bytes

First, let's convert the second value into scientific notation. Notice that 384,000,000,000 is equal to 3.84x10^11. We can think of this as moving the decimal point 11 places to the left while increasing the exponent by 11:

384,000,000,000 = 3.84x10^11

Now we can add the two values:

1.28x10^11 bytes + 3.84x10^11 bytes

When we add these values, we keep the same exponent because we are adding numbers with the same power of 10:

1.28x10^11 + 3.84x10^11 = 5.12x10^11

Therefore, if you buy the additional bytes, your phone will have a total storage of 5.12x10^11 bytes.