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## 1983 Oregon Invitational Mathematics Tournament-PART B2

Have times (e.g. goals, content focus, etc.) changed in mathematics education? One measure is obtained by examining exams from the past.

For example, the following questions are from the "1983 Oregon Invitational Mathematics Tournament." I do not know who produced, coordinated, or scored the exam....as it is one of thousands of items stored in my "MISC" files.

Version: Part B: Number and Calculator Sense Test
Time Limit: 20 minutes for 15 questions
Directions: You can use a calculator (none-graphical at that time). Select right answer, but show your work as it will be used if a tie occurs.
NOTE: Only the final seven of fifteen questions are given below. The first eight were printed last week.

[Q#9] Which is the smallest prime number greater than 450?

[Q#10] Which one of the following is not true for all real numbers x,y?
(a) |x+y| ≤ |x|+|y|
(b) |x-y| ≤ |x|+|y|>br> (c) |x|+|y| ≤ |x+y|
(d) |x|-|y| ≤ |x-y|
(e) |x| ≥ 0

[Q#11] In triangle ABC a2 = b2+c2-2bc cosA. If a = 8, b = 6, and c = 4, calculate cosA correct to decimal places.

[Q#12] When 121212121212 is multiplied by 3579, what are the three middle digits?

[Q#13] When a certain number less than 100 is divided by 5, the remainder is 3; when divided by 2, the remainder is 0; when divided by 4, the remainder is 2; and when divided by 9, the remainder is 6. What is this number?

[Q#14] How many years is 1010 seconds? Take a year to be 365 days. Give the answer correct to the nearest year.

[Q#15] In what digit does 31983 end?

Hint: No hints, as this is a test!

Solution Commentary: An answer key was found with this same test in my files. It claims the answers are as follows:

[Q#9] 457
[Q#10] (c)
[Q#11] -1/4
[Q#12] 181
[Q#13] 78
[Q#14] 317
[Q#15] 7

Do you agree with all of these answers?...think and work carefully....