I am going to assume 10.42 is 10 minutes 42 secons.
10 min * 60 seconds / per minute, = 600 seconds
600 + 42 = 642 seconds starting
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8 min * 60 seconds / per minute, = 480 seconds objective
To solve for how long this will take set up an equation,
642 - 1.6t = 480
162 = 1.6t
t = 101.25 days
Since time has a decial, it needs to be rounded up in order for her to be fully below 8 minutes.
Therefore the answer is 102 days.