ANSWER: y=6
straight lines are 180° and all the angles in a triangle add up to 180°
2 rows of 18 chairs are blue so that is 36 chairs. then 4 rows of 12 chairs are blue so that is 48 chairs 36 plus 48 is 84 total blue chairs
The correct order is:
the probability of heads on 2nd and 4th toss only;
the probability of at least 3 tails in a row;
the probability of 3 or more heads;
the probability of consecutive tails; and
the probability of at least 2 tails.
There are 16 outcomes in the sample space.
There are 8 ways of having consecutive tails; this gives the probability 8/16.
There is 1 way of having heads on the 2nd and 4th toss only, making the probability 1/16.
There are 3 ways to have at least 3 tails in a row, making the probability 3/16.
There are 11 ways to have at least 2 tails, making the probability 11/16.
There are 5 ways to have at least 3 heads, making the probability 5/16.
Start by putting two coins on each side of the scale. If one side is higher, then the light coin must be in that pair (use a second weighing to determine which of that pair is the lightest.)
If the initial weighing shows the two pairs to be even, discard those four and go to the three others. Put two of the coins on the scale - one on each side. If one side stays higher, that coin is your light one. If however they are equal, the final unweighed coin must be the lighter coin.
