One: Party A and Party B start from two places 36 kilometers apart and go in opposite directions. Party A walks 5 kilometers per hour and Party B walks 4 kilometers per hour. Party A started with a puppy, and the puppy walked 16 kilometers every hour. When he meets Party B, the puppy turns and runs to Party A, when he meets Party A, he turns and runs to Party B until they meet. How many roads did the puppy walk?

Meeting time of two people =36÷(5+4)=36÷9=4 (hours).

Distance traveled by the puppy = 16×4=64 (km)

Two brothers and sisters left home for school at the same time. My sister walked 90 meters per minute and my brother walked 60 meters per minute. Big sister walked to the school gate and found that she didn't bring her myopia glasses. She went back to get it at once and met her brother at 0/80 meters from school. How far is the school from home?

When we met, my sister walked more than my brother 180×2=360 (meters).

Meeting time =360÷(90-60)=360/30= 12 (minutes)

Sister's school time =12-180 ÷ 90 =12-2 =10 (minutes).

Distance from school to home =90× 10=900 meters.