2 ¼ jam == menit. detik

1 jam = 60 menit
1 menit = 60 detik

2[tex] \frac{1}{4} [/tex] jam = 2[tex] \frac{1}{4} [/tex] × 60 menit
     = [tex] \frac{9}{4} [/tex] × 60 menit
     = [tex] \frac{540}{4} [/tex] menit
     = 135 menit

2[tex] \frac{1}{4} [/tex] jam = 135 menit
     = 135 × 60 detik
     = 8.100 detik

2[tex] \frac{1}{4} [/tex] jam = 135 menit = 8.100 detik