Answer:D
Step-by-step explanation:
Step-by-step explanation:
since we know, she can run 360 ft per minute, and we want to know how many minutes she would need to run 500 yards we need to find out how often 360 ft fit into 500 yards.
so,
500 yards / 360 ft
how can we make this division ?
help is given to us by taking us that 1 yard = 3 ft.
aha !
so, 500 yards = 500×3 ft = 1500 ft
therefore, our task now looks like
1500 ft / 360 ft
and this we understand and can do, right ?
1500 / 360 = 150/36 = 75/18 = 4 3/18 = 4 1/6 minutes
the closest answer option is therefore 4.2, meaning she would take about 4.2 minutes to run 500 yards.
Answer:
Step-by-step explanation:
Idk look it up
2040 = n/2(20+(n-1)4)
4080 = n(20+4n-4)
4080= 20n +4n^2 -4n
1020 = 4n + n^2
n^2 +4n -1020 =0
use common formula (can't write out so just look at answers. sorry)
which gives answers of n=-34 and n=30. since n can only be positive, n=30 so there are 30 rows. I liked that challenge
