Answer:
Area of trapezium = 1/2 * h (a+b)
here, 480= 1/2 *15*(20+b)
(20+b)=960/15
or, b=64-20
therefore, b= 44
.....
Hope u got it...xd
Since she has seven key the probability that the first one will open the door is

if it takes three attempts to open the door,the probability is

if the three attempts would not work
then the probability that the fourth attempt will open the door is

hope this helps
I honestly don't know, but I think it is 63
6x+4=x-11
x=-3
needs to be 20 characters
Answer:
1g
Step-by-step explanation: