Answer:
let n be the number
then the sum of this number and 7 is
n
+
7
and 3 times this sum is
3
(
n
+
7
)
5 times the number less thirteen is
5
n
−
13
⇒
3
(
n
+
7
)
>
5
n
−
13
←
is the inequality
distribute the brackets on the left side
3
n
+
21
>
5
n
−
13
subtract 3n from both sides
3
n
−
3
n
+
21
>
5
n
−
3
n
−
13
⇒
21
>
2
n
−
13
add 13 to both sides
21
+
13
>
2
n
−
13
+
13
⇒
34
>
2
n
divide both sides by 2
17
>
n
⇒
n
<
17
Step-by-step explanation:
