10 1/2 =
10/1 + 1/2=
2/2 (10/1) + 1/2=
20/2 + 1/2=
21/2
Answer:

Step-by-step explanation:
6 symbols and 4-symbol code so number of combinations wich doesn't contain the same symbol twice would be:
6•5•4•3 = 360
If code starts with a star followed by triangle that means only one posibility for first two symbols and code doesn't containing the same symbol twice means that left 4 symbols for next two.
So number of combinations of code starting with a star followed by triangle and doesn't containing the same symbol twice will be:
1•1•4•3 = 12
The probability that a randomly chosen code starts with a star followed by triangle and doesn't contain the same symbol twice:

Answer:
Step-by-step explanation:
y=2/5x+2
x= 5/2y-5
hopefully this works
There is no question here
Answer:
4:10 and 6:15 are equivalent to 2:5