Answer:
650
Step-by-step explanation:
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!
Let the number of girls be x and the number of boys be y
The number of boys is the same as the number of girls.
x = y
The number of boys is twice the number of girls when 8 girls left.
2(x - 8) = y
x = y ---------------- (1)
2(x - 8) = y -------- (2)
Sub (1) into (2)
2(y - 8) = y
2y - 16 = y
2y - y = 16
y = 16
There were 16 boys and 16 girls initially.
16 + 16 = 32
There were a total of 32 students in the class initially.
Answer:
18
Step-by-step explanation:
you times it
