19 query

course Mth 151

If your solution to stated problem does not match the given solution, you should self-critique per instructions at

http://vhcc2.vhcc.edu/dsmith/geninfo/labrynth_created_fall_05/levl1_22/levl2_81/file3_259.htm

Your solution, attempt at solution. If you are unable to attempt a solution, give a phrase-by-phrase interpretation of the problem along with a statement of what you do or do not understand about it. This response should be given, based on the work you did in completing the assignment, before you look at the given solution.

019. `query 19

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Self-critique (if necessary):

Self-critique Rating:

Question: **** `q query 4.2.6 53812 in expanded form.

What is 53812 in expanded form?

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Your solution:

(5*10^4)+(3*10^3)+(8*10^2)+(1*10^1)+(2*10^0)

Confidence Assessment:

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Given Solution:

`aSTUDENT RESPONSE: (5*10^4) +(2*10^3) + (1*10^2) +(8 * 10^0)

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Self-critique (if necessary):

What is the answer b/c the student response does not look right.

2 means 2 * 10^0

1 means 1 * 10^1

8 means 8 * 10^2

3 means 3 * 10^3

5 means 5 * 10^4

Thus the number 53812 means

(5*10^4)+(3*10^3)+(8*10^2)+(1*10^1)+(2*10^0).

In other words, you were right.

Self-critique Rating:

Question: **** `q query 4.2.20 536 + 279 in expanded notation

Write 536 + 279 in expanded notation.

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Your solution:

536 = (5*10^2) + (3*10^1) + (6*10^0)

279 = (2*10^2) + (7*10^1) + (9*10^0)

(8*10^2) +(1*10^1) + (5*10^0) = 815

Confidence Assessment:

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Given Solution:

`a** We write this sum as

5 * 10^2 + 3 * 10^1 + 6 * 10^0 +

2 * 10^2 + 7 * 10^1 + 9 * 10^0

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8 * 10^2 + 10* 10^1 + 15* 10^0. Since 10 * 10^1 = 10^2 we can write this as

9 * 10^2 + 0 * 10^1 + 15 * 10^0.

Since 15 * 10^0 = 10 * 10^0 + 5 * 10^0 = 10^1 + 5 * 10^0 we rewrite this as

9 * 10^2 + 1 * 10^1 + 5 * 10^0.

This result is expressed in our place-value system as

915. **

5 * 10^2 + 3 * 10^1 + 6 * 10^0 +

2 * 10^2 + 7 * 10^1 + 9 * 10^0

When adding the 6*10^0 and the 9*10^0 I don’t carry the one like in regular math?

We're looking here at the reasons behind the rules we learned in elementary school.

Thus we reason out that 15 * 10^0 means 10 * 10^0 + 5 * 10^0, and since 10 * 10^0 = 10^1 we conclude that our 15 * 10^0 = 1 * 10^1 + 5 * 10^0.

This is the reason you 'carry the 1'.