Select the set in which the numbers are related in the same way as are the numbers of the following sets.

(NOTE : Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g. 13- Operations on 13 such as adding /subtracting /multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

(7, 13, 10)

(15, 21, 18)

(11, 15, 13)

(7, 13, 10)

(15, 21, 18)

The logic followed here is :

(Ist number +  second number ) ÷ 2 = IIIrd number

As

(7 +  13 ) ÷ 2 =10

(15 +  21 ) ÷ 2 =18

Same as in option 3 (11, 15, 13)

(11 +  15 ) ÷ 2 = 13