Hello Math Question exercise be4 tommorow test

Test Preparation
1

<p>If n and p are integers greater than 1 and if p is a factor of both n+3 and n+10, what is the value of p??</p>

<p>A) 3
B 7
C 10
D 13
E 30</p>

<p>I dont understand what they mean with "factor of", please can someone explain it?</p>

<p>Thanks </p>

<p>Kent</p>

2

<p>b
u
u
m
m
p
p</p>

3

<p>n+3=k1 * p .... (1), K1 is some unknown integer</p>

<p>n+10 = k2 * p ... (2), k2 is some unknown integer</p>

<p>(2) - (1)</p>

<p>7= p * ( k2-k1)</p>

<p>7 can only be factored as 7 * 1, and since p > 1 so P has to be 7</p>

<p>Hope that helps.</p>

4

<p>"p is a factor of n+3" means that n+3 is evenly divisible by p.</p>

<p>One way to solve this is to just start making up numbers for n to see if n+3 and n+10 have a factor in common:
if n=1 , n+3=4 and n+10=11. 4 and 11 have no factor >1 in common.
if n=2 , n+3=5 and n+10=12. 5 and 12 have no factor >1 in common.
if n=3 , n+3=6 and n+10=13. 6 and 13 have no factor >1 in common.
if n=4 , n+3=7 and n+10=14. 7 and 14 have one factor >1 in common: 7. So p=7.</p>

5

<p>yep good job PETE...and well this was in collegeboard book lol</p>