128.34
= 128+ 0.34
= 128+ 34/100
= 128+ (34/2) / (100/2)
= 128+ 17/50
= 128 17/50
128.34 written as a mixed number is 128 17/50~
At least 8 routes, at most 63 routes
Let:
v = Olga's speed
t = the time Anna spent going to school (3 km/hour)
t/2 = the time Anna spent running back home with speed of 6 km/hour
So, t + t/2 = 3t/2 is the total time
In the meantime distance = speed*time and the both made the same distance we can put it as:
3t + 6*(t/2) = (3t/2)*v
6t = (3/2)tv divide both sides by t
(3/2)v = 6
v = 2*6/3
v = 4 km/hour
Olga's speed was 4 km/hour.
4 x 7= 28
BTW no calculator. Did it in my head. Hope this helps!
