RRB NTPC CBT 2 Level 6 Exam 9 May 2022 Shift 2

Question : 116 of 120

Marks: +1, -0

When k > 0, is subtracted from each of 11, 15, 20 and 30, the numbers so obtained in this order are in proportion. What is the mean proportional between (2k + 2) and 3k²?