Mr Daniels Maths
Probability Trees

Set 1

Set 2

Set 3

Q1) There were 4 purple pencils ,and 8 blue pencils in a tray . Two pencils were picked and not replaced. What was the probability they were both purple ?
[ \(\frac{1}{11}\) ]

Q1) There were 9 red pens ,and some green pens in a draw . Two pens were picked at random and not replaced. The probability they were both red was \(\frac{6}{11}\). How many green pens were there ?
[ 3 ]

Q1) There are two colour of sweets in a bag. There are 5 more red sweets than blue . Two sweets are picked at random and not replaced.The probability they are both the same is \(\frac{11}{21}\). The number of blue sweets is less than 10. How many red sweets are there ?
[ 10 ]

Q2) There were 8 green pens ,and 5 blue pens in a tin . Two pens were picked and not replaced. What was the probability they were both green ?
[ \(\frac{14}{39}\) ]

Q2) There are 8 purple pencils ,and some red pencils in a packet . 4 extra red pencils were added. Two pencils were picked at random and not replaced. The probability they were both purple was \(\frac{7}{30}\). How many red pencils were there to begin with ?
[ 4 ]

Q2) There are 9 green apples ,and some purple apples in a packet. Two apples were picked at random from the packet and not replaced. The probability they are both the different is \(\frac{6}{13}\). How many purple apples were there ?
[ 4 ]

Q3) There were two colour of beads in a tray. There were 9 green beads ,and 3 blue beads. Two beads were picked and not replaced. What was the probability they were both the same colour ?
[ \(\frac{13}{22}\) ]

Q3) There were 10 blue pens ,and some yellow pens in a draw . Two pens were picked at random and not replaced. The probability they were both blue was \(\frac{3}{8}\). How many yellow pens were there ?
[ 6 ]

Q3) There are 8 yellow sweets ,and some green sweets in a tray. Two sweets were picked at random from the tray and not replaced. The probability they are both the different is \(\frac{16}{45}\). How many green sweets were there ?
[ 2 ]

Q4) There were two colour of beads in a box. There were 4 yellow beads ,and 8 purple beads. Two beads were picked and not replaced. What was the probability they were both the same colour ?
[ \(\frac{17}{33}\) ]

Q4) There are 9 green beads ,and some purple beads in a bag . 4 extra purple beads were added. Two beads were picked at random and not replaced. The probability they were both green was \(\frac{12}{35}\). How many purple beads were there to begin with ?
[ 2 ]

Q4) There were 9 yellow beads ,and some green beads in a bag. Two beads were picked at random from the bag and not replaced. The probability they were both the same is \(\frac{13}{22}\). How many green beads were there ?
[ 3 ]

Q5) There were two colour of pencils in a tray. There were 7 blue pencils ,and 5 purple pencils. Two pencils were picked and not replaced. What was the probability they were both the same colour ?
[ \(\frac{31}{66}\) ]

Q5) There are 7 red pencils ,and some purple pencils in a bag . 7 extra purple pencils were added. Two pencils were picked at random and not replaced. The probability they were both red was \(\frac{21}{190}\). How many purple pencils were there to begin with ?
[ 6 ]

Q5) There were 6 blue pencils ,and some yellow pencils in a tray. Two pencils were picked at random from the tray and not replaced. The probability they were both the same is \(\frac{1}{2}\). How many yellow pencils were there ?
[ 10 ]