The Solution:
From the given picture,
Step 1 has 5 dots
Step 2 has 6 dots
Step 3 has 7 dots
Clearly, we can see that the sequence is a linear sequence.
By the formula for finding the nth term of an arithmetical Progression, which is
[tex]T_n=a+(n-1)d[/tex]
To find the number of dots in the 9th step, we shall use the above formula.
Where,
[tex]\begin{gathered} d=\text{ number of dots in step2-number of dots in step1} \\ d=6-5=1 \\ a=5\text{ (number of dots in step1)} \\ n=28 \\ T_{28}=28th\text{ step} \end{gathered}[/tex]
Substituting these values in the formula above, we get
[tex]\begin{gathered} T_{28}=5+(28-1)1 \\ =5+27 \\ =32\text{ dots} \end{gathered}[/tex]
So, The 28th step has 32 dots.
Therefore, the correct answer is 32 dots.
