Any one of the runners could be 1st.
Every runner except for the one that was 1st could be 2nd.
Every runner that wasn't 1st or 2nd could be 3rd.
100*99*98=970200 groups.
This involves permutations because order does matter.
Hope this helps!
The should be 158 ways, because 9*8+8*7+6*5=158.
T
adds 6
t-6
divides by 6
(t-6)/6
shawn
7+t
divide by 7
(7+t)/7
theyare equal
(t-6)/6=(7+t)/7
times 42 both sides
7(t-6)=6(t+7)
distribute
7t-42=6t+42
minus 6t both sides
t-42=42
add 42 both sides
t=84
In the step after -6x+10=4x+20, he moved the terms incorrectly. you have to add 6x to both sides so it would be 10=4x+6x+20 which simplifies to 10=10x+20. subtract 20 from both sides to get -10=10x. divide both sides by 10. the answer is x=-1
Answer:
Gary had four cookies after Sally gave him her cookies he had ten. How many cookies did Sally give him?
