36
a= 1/2 b x h
= 5cm x 72cm
= 360cm
If b is in the first position then c can be in any 1 of the remaining 6 positions.
If we start with ab then the letter c can be in any one of 5 positions and if we have aab there are 4 possible positions for c and so on.
So the total number of possible sequences where b comes first = 6+5+4+3+2+1 = 21.
The same argument applies when c comes before b so that gives us 21 ways also.
So the answer is 2 *21 = 42 different sequences.
A more direct way of doing this is to use factorials:-
answer = 7! / 5! = 7 * 6 = 42.
( We divide by 5! because of the 5 a's.)
Answer:
936 is the correct option
125 is equivalent to
<em>1.25</em>
<em>1 1/4 </em>
<em></em>
Pick either one... 1.25 is more likely to be correct
<em></em>
<em></em>
Answer:
I agree that this question can be confusing:
Apparently point A and point B must be on the same straight line (measured from the light house or the question would be nonsensical)
tan 13 = H / DA where H is height of lighthouse
tan 8 = H / DB tangent measured from point B
tan 13 / tan 8 = DB / DA
DB = .2309 / .1405 * 1279 = 2101 ft
DB - DA = 2101 - 1279 = 822.0 ft
