3 men finish painting a wall in 8 days. Four boys do the same job in 7 days. In how many days will 2 men and 2 boys working together paint two such walls of the same size?

a) 6 6/13 days

b) 3 3/13 days

c) 9 2/5 days

d) 12 12/13 days

• 1 man's 1 day work=1/24
  1 boy's 1 day work=1/28
  2 men's 1 day work=(1/24)*2=1/12
  2 boys 's 1 day work = (1/28)*2=1/14
  2 men and 2 boys work together=1/12+1/14
  =(7+6)/84
  =13/84
  no of days taken by 2 men and 2 boys=84/13
  6 6/13
  Option (a) is the ans
• 7 years agoHelpfull: Yes(9) No(1)
• 3men 8days -->1 man=1/24 days(1/3*1/8)
  4boys 7days-->1 boy=1/28 days
  2men+2boys==2/24+2/28-->1/12+1/14
  2 such walls-->1/24+1/28
  take LCM, 13/168
  reciprocal of it, 168/13
  i.e,12 12/13
  
• 11 years agoHelpfull: Yes(5) No(10)
• For one wall ans is 6 6/13,but they asked to find it for two such walls.so,ans is 12 12/13
• 5 years agoHelpfull: Yes(1) No(0)
• 1 man's 1 day work=1/24
  1 boy's 1 day work=1/28
  2 men's 1 day work=(1/24)*2=1/12
  2 boys 's 1 day work = (1/28)*2=1/14
  2 men and 2 boys work together=1/12+1/14
  =(7+6)/84
  =13/84
  no of days taken by 2 men and 2 boys=84/13
  6 6/13
  Option (a) is the ans
• 5 years agoHelpfull: Yes(0) No(1)