160 adults and 80 students seems to be correct
Answer:
An atom of sodium has 11 proton, 11 electrons, and 12 neutrons.
B = block p = park
2b + p = 10 min 2 runs around the block takes 10 minutes
2b + 3p = 22 min 2 runs around the block plus 3 runs around the park takes 22 minutes
To solve, I will use substitution. First, I will divide the first equation by 2 to get b by itself and subtract p from both sides to get b by itself. Then, substitute 5 - 1/2p in for b in the second equation because they have equal values. Then, subtract 10 from both sides to eliminate it. Divide by 2 to both sides to get 'p' by itself.
2b + p = 10 min ---------→b + 1/2p = 5 ----------→ b = 5 - 1/2p
2(5 - 1/2p) + 3p = 22 ---------→ 10 -p + 3p = 22 --------→ 10 + 2p = 22
10 + 3p = 22 ----------→ 2p = 12
2p = 12 -------------→ p = 6
It takes 6 minutes to jog around the park
Hope this helps!
Answer:
10 tacos costs $15.00
Step-by-step explanation:
I like to use ratio's to solve this type of problem. I will put cost over number of tacos.
$6.00 x dollars
-------- = --------------
4 tacos 10 tacos
Using cross products
6 * 10 = 4 * x
60 = 4x
Divide each side by 4
60/4 = 4x/4
15 =x
10 tacos costs $15.00
