(5/6-5/8+1/12)*24
=(5/6)*24-(5/8)*24+(1/12)*24
=5*4-5*3+1*2
=20-15+2
=7
4/(8/3)-0.6
=4*(3/8)-0.6
=6-0.6
=5.4
9/10+(3/8)/(5/4)-1/5
=9/10+(3/8)*(4/5)-1/5
=9/10+3/10-1/5
=12/10-1/5
=6/5-1/5
=1
(5/14)/(4/21)*0.64
=(5/14)*(21/4)*0.64
=(15/8)*0.64
=15*0.08
=1.2
624-197
=624-(200-3)
=624-200+3
=427