Inaccurate 34503

Peter has an inaccurate alarm clock. He found that he was exactly 4 minutes late every hour. At 21:30 in the evening, he will set the exact time for it. What must alarm time be on him to wake him up at exactly 06:30?

Result

t₂ = 7:06

Step-by-step explanation:

$$\begin{gathered} t_1=6\frac{30}{60}=6+\frac{30}{60}=\frac{6\cdot 60+30}{60}=\frac{360+30}{60}=\frac{390}{60}=\frac{13}{2}=6\frac{1}{2}=6.5 \\ {h}_1=21\frac{30}{60}=21+\frac{30}{60}=\frac{21\cdot 60+30}{60}=\frac{1260+30}{60}=\frac{1290}{60}=\frac{43}{2}=21\frac{1}{2}=21.5 \\ h=(t_1+24)-h_1=(\frac{13}{2}+24)-\frac{43}{2}=9\text{h} \\ {t}_2=t_1+h\cdot \frac{4}{60}=\frac{13}{2}+9\cdot \frac{4}{60}=7.1=7:06 \end{gathered}$$

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