A boy riding a Thomas the Tank Engine scooter and a girl riding a pink scooter are on the sidewalk .
It is improbable that a boy and girl on scooters are racing side by side down a vacant sidewalk .
It is probable that a boy and girl on scooters are racing side by side down a vacant sidewalk .
It is improbable that a boy and girl on scooters are racing side by side down a vacant sidewalk .
A boy and girl on scooters are racing side by side down a vacant sidewalk .