Select the odd group of numbers. (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 Isubtracting /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 - 70 - 1600)

The logic followed here is :

Ist number × 10 = second number and second number× 20 = IIIrd number

(6 - 60 - 1200) = 6 × 10 = 60 and 60 × 20 = 1200

(7 - 70 - 1600) = 7 × 10 = 60 and 70 × 20 = 1400 but 1600 is given (odd)

(5 - 50 - 1000) = 5 × 10 = 50 and 50 × 20 = 1000

(4 - 40 - 800) = 4 × 10 = 40 and 40 × 20 = 800