Hello.
First of all, let the number be t.
8 times t can be written like this:

Notice that the number is before the variable and the times sign (×) is not there.
We can write it as 8×t, but we usually write it as 8t.
The sum of means we add:
8t+21
Now, "less than" is "<" :

Therefore, the answer is

I hope it helps.
Have a nice day.

$750000 for all 10 years and $375000 for just ten years
Answer:
+
Step-by-step explanation:
We sure can write 2^2/5+ 3^1/10 as 
// use the
to transform the expression
Convert
to
=
(here a = 2, n = 5, m = 2)
Then convert
to
=
(here a = 3, n = 10, m = 1)
Now we get
=
+
. This is the simplified form, which is the answer.
Youre correect answer is 70