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A bag contains six 10-rupee coins, four 5-rupee coins and two 1-rupee coins. Six coins are drawn without replacement with each coin equally likely to be chosen. What is the probability that the coins add up to a value of at least 48 rupees?
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• 59/924
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• 127/924
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• 194/924
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• 91/924
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• 37/924

Read Solution (Total 3)

127/924
given 6 coins of 10 Rs.
4 coins of 5 Rs. & 2 coins of 1 rs.
Since we have to select only 6 coins of any kinds to fullfill the condition we can select 6 coins as follows
6C6 for 60,6C5AND4C1 for 55,6C5AND2C1 for 51,6C4AND4C2 for 50
so total possible events are 6c6+6c5*4c1+6c5*2c1+6c4*4c2=127
total eway of selecting 6 coins are (6+4+2)C6=924
hence probability is =possible way/total way=127/924
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12 years agoHelpfull: Yes(46) No(9)

Denomination: 10 5 1

possibilities: 6=>6C6 0 0 =>1
5=>6C5 1=>4C1 0 =>24
4=>6C4 0 1=>2C1 =>12
4=>6C4 2=>4C2 0 =>90
SUM : ======>127
12 years agoHelpfull: Yes(2) No(0)
127/924.......
12 years agoHelpfull: Yes(0) No(0)

TCS Other Question

A calculator has a key for squaring and one for inverting. So if x is the displayed number, then pressing the square key will replace x by x2 and pressing the invert key will replace x by 1/x. If initially the number displayed is 6 and one alternately presses the invert and square key 16 times each, then the final number displayed (assuming no roundoff or overflow errors) will be
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• 6 -(216)
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• 6((-2)16)
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• 6 -32
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• 632
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• 6((-1)1632) In a 3*3 square grid comprising 9 tiles each tile can be painted in red or blue color. When the tile is rotated by 180 degree, there is no difference which can be spotted. How many such possibilities are there?
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