There are 200 questions on a 3 hr examination.Among these questions are 50 mathematics problems.It is suggested that twice as much time be spent on each maths problem as for each other question.How many minutes should be spent on mathematics problems

A.36 B.72 C.60 D.100

• let s be the min to solve the ordinary question so,150x+50(2x)=180
  so, x=18/25 for solving 150 questions 150*18/25=108,
  so for solving a mathamatics problem 72 min(180-108) taken. Ans is 72 min
• 13 years agoHelpfull: Yes(83) No(1)
• if x mins are spent on other qns, then
  250x =180
  x=180/250= 18/25 mins
  time spent on maths probs= 2*50*18/25= 72 mins
  
• 13 years agoHelpfull: Yes(15) No(4)
• time on each maths qn = 2*180/250 = 36/25 mins
  Time for all 50 maths qns = 50*36/25 =72 mins
• 13 years agoHelpfull: Yes(6) No(2)
• 50 ques are of maths so,
  150 are remaining..
  let x be the time spent on each of other questions...
  then 2x is spent on each maths ques...
  so, 150*x + 50*2x = 3*60min
  250x=180min
  x=18/25 mins
  but time spent on each maths prb is 2xi.e, 2(18/25 ) mins
  total time spent on 50 maths problems is 2* 50 (18 / 25 ) mins
  =72 mins..
• 10 years agoHelpfull: Yes(4) No(1)
• 50 ques are of maths so,
  150 are remaining..
  let x be the time spent on each of other questions...
  then 2x is spent on each maths ques...
  so, 150*x + 50*2x = 3*60min
  250x=180min
  x=18/25 mins
  but time spent on each maths prb is 2xi.e, 2(18/25 ) mins
  total time spent on 50 maths problems is 2* 50 (18 / 25 ) mins
  =72 mins..
• 5 years agoHelpfull: Yes(1) No(0)