+0  
 
0
2073
1
avatar

How many positive integers less than 500 are the product of exactly
two distinct (meaning different) primes, each of which is greater than 10?

Guest Mar 5, 2015

Best Answer 

 #1
avatar+20680 
+6

How many positive integers less than 500 are the product of exactly
two distinct (meaning different) primes, each of which is greater than 10 ?

 

$$\small{\text{
$
\begin{array}{r|rcl|r}
\hline
n & p_1 & & p_2 & p_1\cdot p_2 \\
\hline
1 & 11 & \cdot & 13 & = 143 \\
2 & 11 & \cdot & 17 & = 187 \\
3 & 11 & \cdot & 19 & = 209 \\
4 & 11 & \cdot & 23 & = 253 \\
5 & 11 & \cdot & 29 & = 319 \\
6 & 11 & \cdot & 31 & = 341 \\
7 & 11 & \cdot & 37 & = 407 \\
8 & 11 & \cdot & 41& = 451 \\
9 & 11 & \cdot & 43 & = 473 \\
10 & 13 & \cdot & 17 & = 221 \\
11 & 13 & \cdot & 19 & = 247 \\
12 & 13 & \cdot & 23 & = 299 \\
13 & 13 & \cdot & 29& = 377 \\
14 & 13 & \cdot & 31 & = 403 \\
15 & 13 & \cdot & 37 & = 481 \\
16 & 17 & \cdot & 19 & = 323 \\
17 & 17 & \cdot & 23 & = 391 \\
18 & 17 & \cdot & 29 & = 493 \\
19 & 19 & \cdot & 23 & = 437 \\
\hline
\end{array}
$
}}$$

heureka  Mar 5, 2015
 #1
avatar+20680 
+6
Best Answer

How many positive integers less than 500 are the product of exactly
two distinct (meaning different) primes, each of which is greater than 10 ?

 

$$\small{\text{
$
\begin{array}{r|rcl|r}
\hline
n & p_1 & & p_2 & p_1\cdot p_2 \\
\hline
1 & 11 & \cdot & 13 & = 143 \\
2 & 11 & \cdot & 17 & = 187 \\
3 & 11 & \cdot & 19 & = 209 \\
4 & 11 & \cdot & 23 & = 253 \\
5 & 11 & \cdot & 29 & = 319 \\
6 & 11 & \cdot & 31 & = 341 \\
7 & 11 & \cdot & 37 & = 407 \\
8 & 11 & \cdot & 41& = 451 \\
9 & 11 & \cdot & 43 & = 473 \\
10 & 13 & \cdot & 17 & = 221 \\
11 & 13 & \cdot & 19 & = 247 \\
12 & 13 & \cdot & 23 & = 299 \\
13 & 13 & \cdot & 29& = 377 \\
14 & 13 & \cdot & 31 & = 403 \\
15 & 13 & \cdot & 37 & = 481 \\
16 & 17 & \cdot & 19 & = 323 \\
17 & 17 & \cdot & 23 & = 391 \\
18 & 17 & \cdot & 29 & = 493 \\
19 & 19 & \cdot & 23 & = 437 \\
\hline
\end{array}
$
}}$$

heureka  Mar 5, 2015

11 Online Users

avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.