Difference between revisions of "1967 AHSME Problems/Problem 1"
Silvernight (talk | contribs) (Created page with "==Problem== The three-digit number <math>2a3</math> is added to the number <math>326</math> to give the three-digit number <math>5b9</math>. If <math>5b9</math> is divisible by...") |
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==Solution== | ==Solution== | ||
− | If <math>5b9</math> is divisible by <math>9</math>, this must mean that <math>5 + b + 9</math> is a multiple of <math>9</math>. So, < | + | If <math>5b9</math> is divisible by <math>9</math>, this must mean that <math>5 + b + 9</math> is a multiple of <math>9</math>. So, <cmath>5 + b + 9 = 9, 18, 27, 36...</cmath> |
− | <math> | + | Because <math>5 + 9 = 14</math> and <math>b</math> is in between 0 and 9, |
− | < | + | <cmath>5 + b + 9 = 18</cmath> |
+ | <cmath>b = 4</cmath> | ||
+ | |||
+ | The question states that | ||
+ | <cmath>2a3 + 326 = 549</cmath> | ||
+ | so | ||
+ | <cmath>2a3 = 549 - 326</cmath> | ||
+ | <cmath>2a3 = 223</cmath> | ||
+ | <cmath>a = 2</cmath> | ||
+ | |||
+ | <cmath>a + b = 6</cmath> | ||
+ | which is answer choice <math>\boxed{C}</math>. | ||
==See Also== | ==See Also== | ||
− | {{AHSME | + | {{AHSME 40p box|year=1967|before=First Question|num-a=2}} |
[[Category:Introductory Algebra Problems]] | [[Category:Introductory Algebra Problems]] | ||
+ | {{MAA Notice}} |
Latest revision as of 00:45, 16 August 2023
Problem
The three-digit number is added to the number to give the three-digit number . If is divisible by 9, then equals
Solution
If is divisible by , this must mean that is a multiple of . So,
Because and is in between 0 and 9,
The question states that so
which is answer choice .
See Also
1967 AHSC (Problems • Answer Key • Resources) | ||
Preceded by First Question |
Followed by Problem 2 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 • 26 • 27 • 28 • 29 • 30 • 31 • 32 • 33 • 34 • 35 • 36 • 37 • 38 • 39 • 40 | ||
All AHSME Problems and Solutions |
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