How to simplify the calculation

How to simplify the calculation

Original formula = 17 / 10 * 7 / 2-3 / 2 * 7 / 2
=1.7*3.5-1.5*3.5
=3.5（1.7-1.5）
=3.5*0.2
=0.7
Original formula = 99 * 38 + 18 / 19 * 38-3700
=100*38-38+36-3700
=3800-3700-38+36
=100-2=98
Original formula = 138 / 139 * (139 + 1)
=138+138/139

Number reasoning: 99 26 38 - 11 19 - 18 ()
Options: a 18 B 36 C 54 D72
What's the rule here?

Choose a!
99+26=125=5*5*5
26+38=64=4*4*4
38-11=27=3*3*3
-11+19=8=2*2*2
19-18=1=1*1*1
So. - 18 + 18 = 0 = 0 * 0 * 0

99 26 38 - 11 19 - 18 what's the next number?

99+26=125=5*5*5
26+38=64=4*4*4
38-11=27=3*3*3
-11+19=8=2*2*2
19-18=1=1*1*1
-18+18=0=0*0*0
99 26 38 - 11 19 - 18 the next number is 18

What is 0.99 times 1024

1 013.76