Answer:
= 5n - 2
Step-by-step explanation:
The nth term of an arithmetic sequence is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₄ = 18 , then
a₁ + 3d = 18 , that is
3 + 3d = 18 ( subtract 3 from both sides )
3d = 15 (divide both sides by 3 )
d = 5
Then
= 3 + 5(n - 1) = 3 + 5n - 5 = 5n - 2 ← explicit rule
If this is for a better deal if you made the prices the same so instead of 5 for six itd be 50 for $60 and 8 for $10 would be 48 for $60 obviously 5 for 6 is the best choice. thats just how i was taught i hoped this helps
Answer:
21/4 :3/4= 21/4 *4/3= 7/1 *1/1 = 7
7 bookcases
Step-by-step explanation: