Question

At 't' minutes past 2pm , the time needed by the minute hand of a clock to show 3pm was found to be 3minutes less than t^2/4 find 't'.

Answer 1

Solution -:According to condition we have
Given time needed by the minutes hand show (t²/4) – 3
Hence the quadratic equation becomes, (t²/4) – 3 = 60 – t Because 2 pm to 3pm it will be 60 minutes.
(t² – 12)/4 = 60 – t
(t² – 12) = 240 – 4 t
t² – 12 – 240 + 4 t = 0
t² + 4t – 252 = 0
t² + 18t – 14t – 252 = 0
t(t + 18) – 14(t + 18) = 0
(t + 18)(t – 14) = 0
(t + 18) = 0 or (t – 14) = 0
∴ t = - 18 or t = 14 we will neglect t=-18 so we will have answer t= 14 minutes.