AFCAT I 23 Jan 2025 Shift 1 Paper

If upstream speed =U and downstream speed =D, then speed of boat =(U+D)∕2
Calculation:
According to the question,
‌20∕U+44∕D=8
‌15∕U+22∕D=5
Multiply by 2 the equation (ii) then subtract from 1 we get
‌20∕U+44∕D=8
‌

30∕U+44∕D=10

‾

‌−10∕U=−2
‌⇒U=5km∕hr
Putting the value in equation (i), we get D=11
So, the speed of boat =(U+D)∕2=(5+11)∕2=8km∕hr
∴ The correct answer is 8km∕hr