If a student decrease his speed by 25% of original seed, he reach school 8 minute late. What is his usual time of reaching school (in minutes)? (A) 28 (B) 30 (C) 20 (D) 24 (E) 32

• as we know the speed of student is decreased by 25%
  so,
  Speed left = (overall speed -decreased speed)/(overallspeed)
  speed left = 75/100 =3/4.
  speed is inversely proportional to time it means, S =1/T
  then
  3/4s =4/3t
  so,
  from above question
  4t/3-t = 8/60
  t=2/5
  t= 2/5*60 = 24MINUATEs
  hence answer is 24 minuates
• 5 years agoHelpfull: Yes(7) No(1)
• 100t=75t(t-8)
  t=24
• 5 years agoHelpfull: Yes(3) No(1)
• If he decrases 25% i was 8 minutes lates then in 25 minutes he will walk 8 then for 100 it wiil be 8*4=32
• 5 years agoHelpfull: Yes(2) No(4)
• st=s*(75/100)(t+8)
  t=3/4(t+8)
  4t=3t+24
  t=24 min
• 5 years agoHelpfull: Yes(2) No(0)