Anna and Yao are apart. They jog towards each
other along a straight road. Anna jogs at a constant rate of and Yao jogs at a constant
rate of . When they
meet, how much farther has Yao travelled than Anna?
, 2026
Pick one
Solution
Solution 1:
Each hour, Anna jogs
and Yao jogs , and so
combined they jog km}$.
After hours, they combine to jog
,
and after hours, they combine to
jog
km}$.
Since they started
apart, then after hours they
meet. After hours, Anna has
jogged km}
km} km}$
farther than Anna.
Solution 2:
Anna jogs at and
Yao jogs at , and so
they are moving toward one another at a constant rate of
km/h}$.
Thus combined Anna and Yao will travel , and meet after
hours.
Since Yao jogs km/h}$ faster than Anna jogs, then Yao travels
km}$ farther than Anna.
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