MATH 156

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I need help with this question I'm reviewing for my final for next week. Thanks

Perform the indicated operation.
(84) ÷ [(-1) - (-7)]

AND

Find the GCF of the numbers using an appropriate method.
240, 10,000, and 4500

AND

Write the number in scientific notation.0.000 294

Thank you

• MATH 156 -

1. Start by performing operations in the parentheses:
84 / [-1 + 7]
A negative multiplied by a negative is a positive.

Now we have 84/[6], which equals 14

2. Start by finding prime factors of the numbers:
240 = 4*6*10 = 2^2 * 2 * 3 * 2 * 5 = 2^4 * 3 * 5
10000 = 10^4 = 2^4 * 5^4
4500 = 9 * 5 * 100 = 3^2 * 5 * 10^2 = 3^2 * 5 * 2^2 * 5^2 = 3^2 * 5^3 * 2^2

Now look for common factors in the prime factorizations:
240 = 2^4 * 3 * 5
10000 = 2^4 * 5^4
4500 = 3^2 * 5^3 * 2^2

The greatest power of 2 shared by all of them is 2^2.
The greatest power of 3 shared is 3^0.
The greatest power of 5 shared is 5^1. Therefore, the GCF is 2^2 * 3^0 * 5^1 = 4*1*5 = 20

3. 0.000294. Multiply by 10 until there is a number in the units place:
.000294 * 10 = .00294
.00294 * 10 = .0294
.0294 * 10 = .294
.294 * 10 = 2.94

You multiplied by 10 four times. Therefore, the number is 2.94 x 10^(-4) in scientific notation.

• MATH 156 -

Thank you so much it makes a lot more sense to me now. I have my final exam next week so I reviewing over my work. Once again thank you

• MATH 156 -

I have a question what do you mean by ^ what does that symbol mean I know that * means multiplication.

• MATH 156 -

^ means to the power of.

For instance, 4^2 is 4 squared and 5^3 is 5 to the third power or 5 cubed.

• MATH 156 -

Has the content in this course allowed you to think of mathematics as a useful tool? If so, how? What concepts investigated in this course might apply to your personal and professional life?

• MATH 156 -

what is the answer if I use lattice multiplication to find the product in 124 x 56