Question

Question #a2b1c

Answer 1

a) The girl will arrive before curtain time.
b)

Explanation:

Total distance to be traveled:
`color(white)("XXX")1000 m + 1700 m = 2700 m`
Time until curtain opens:
`color(white)("XXX")8" min" = 480" sec."`

Period 1
Car travels `1000" m"` at `(25" m")/"sec"`

Time taken:
`color(white)("XXX")1000" m"xx"sec"/(25" m") = 40 " sec."`

Period 2
Car waits at traffic light for `1.5" min" = 90" sec."`
(Total time: `40+90=130 " sec."`)
(Distance traveled this period: `0`)
(Total distance traveled: `1000" m"`)

Period 3
Car travels `1700" m" at (10" m")/"sec"`

Time taken:
`color(white)("XXX")1700" m"xx"sec"/(10" m")=170 " sec."`
(Total time: `40+90+170 = 300 " sec"`)
(Distance traveled this period: `1700" m"`)
(Total distance traveled: `1000 + 1700 = 2700" m"`)