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Look at the steps and find the pattern.step 1step 2step 3How many dots are in the 28th step?dots

Look at the steps and find the pattern.step 1step 2step 3How many dots are in the-example-1
User Dotnethaggis
by
2.5k points

1 Answer

10 votes
10 votes

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


T_n=a+(n-1)d

To find the number of dots in the 9th step, we shall use the above formula.

Where,


\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}

Substituting these values in the formula above, we get


\begin{gathered} T_(28)=5+(28-1)1 \\ =5+27 \\ =32\text{ dots} \end{gathered}

So, The 28th step has 32 dots.

Therefore, the correct answer is 32 dots.

User Manish Sapariya
by
3.4k points