If it took 2 hours to clean 5 houses, how many houses could be cleaned in 6 hours?

Answer this question only if you know the 30 points and

Haruka hiked several kilometers in the morning. she hiked only 66 kilometers in the afternoon, which was 25% less than she had hiked in the morning. how many kilometers did haruka hike in all?

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'