I hope this helps you
distance=speed×time
first cars time t
second cars time t+3
same distance
distance=55.t
distance=40. (t+3)
55t=40 (t+3)
55t-40t=120
15t=120
t=8
t+3=11
Answer:
Median
Step-by-step explanation:
Hope this helped
You just need to plug those expressions inside the formula: it doesn't matter if they're expressions involving a variable instead of plain numbers: the formula becomes

If you want, you can simplify it by expanding the square and then multiply the two parenthesis:

Answer:
¼
Step-by-step explanation:
The probability of having a boy is ½ and that of a girl is ½.
Probability of boy, boy is (pb*pb) and given pb to be ½ then we can prove the point as follows
For these two children
The options are as follows
1 boy(first) and 1 girl
2 boys
2 girls
1 girl( first) and 1 boy
These are four possible options and the option for two boys is 1 out of the four.
The probability of 2 boys is ½*½=¼
R is greater then or equal to18