Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
Mathematics
Mathematics
Problem
6. Explain why
7
×
11
×
13
+
13
7 \times 11 \times 13+13
7
×
11
×
13
+
13
and
7
×
6
×
5
×
4
×
3
×
2
×
1
+
5
7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1+5
7
×
6
×
5
×
4
×
3
×
2
×
1
+
5
are composite numbers.
Browse the problem library