Lesson check
1. use comparative relational thinking to
choose which equation is true.
a. 56 + 42 = 63 +49
b. 87 + 55 = 91 + 51
c. 61 - 37 = 57 – 41
d. 77 - 39 = 85 - 31 v

Abus travels 280km south along a straight path with an average velocity of 88km/h to the south. the bus stops for 24 min, then it travels 210 km south with an average velocity of 75 km/h to the south. how long does the total trip last?