How much more did Leroy pay than Cora?​

Leroy paid 49.07 more than Cora.

Step-by-step explanation:

Let LeRoy's bill be x

Let Cora's bill be y

3*y - 8.59 = x        (1)

x + y = 68.29        (2)

Substitute the value of x in (1) into the value of x in (2)

3y - 8.59 + y = 68.29          Combine the ys

4y - 8.59 = 68.29                Add 8.59 to both sides

   + 8.59     8.59

4y = 76.88                           Divide by 4

4y/4 = 76.88/4

y = 19,22

x + y = 68.29                      Substitute 19.22 for y

x + 19.22 = 68.29               Subtract 19.22 from both sides

  - 19.22   -19.22

x =              49.07

three-fourths of an hour

36÷48=0.75

0.75=

a. 12.5 kg

step-by-step explanation:

f = ma

so

m = f/a = (2500 n)/(200 m/s²) = 12.5 kg

1 n = 1 kg·m/s²