Which of the following is most likely the next step in the series 5a, 10b, 15c, 20d

The given series ⇒ 5a, 10B, 15c, 20D

Each term consists of a number and letter.

It may be divided into (5 , 10 , 15 , 20 , ) and ( a , B , c , D , )

The series of numbers is arithmetic series.

The first term (a) is 5 and the common difference (d) is 5

It has a general equation = a + (n-1)d

So, next step in the series is the fifth term = a + (5-1)d = 5 +(5-1) ×5 = 25 ⇒⇒ (1)

The series of letters is the sequence of letters from a to z but with the sequence is ( capital , small , capital , )

So, next step in the series will be the letter after D in small case

Which is = e ⇒⇒(2)

From (1) and (2)

∴ The next step in the series ( 5a, 10B, 15c, 20D) is ⇒⇒⇒ 25e  

Option 1 is correct that is x=17.

Step-by-step explanation:

We have been given the information:

122 is decreased by 5 times a number.

The result is equal to number increased by 20

let the number be x

So, according to the question equation becomes:

122-5x =x+20

We will solve for x to get the number:

Rearranging the terms

122-20= x+5x

On simplification:

102 =6x

so, x will be 102/6 =17

hence, option 1 is correct.