Below * * *, there are six small problems, one of which is not simple, and the other five problems can be simply calculated.

2.02x8.5 (simple)

=(2+0.O2)X8.5

=2x8.5+0.02x8.5

= 17+0. 17

= 17. 17

56x 1.25 (simple)

=7x(8x 1.25)

= 7Xl0

=70

L.25+4.6 10.75 (simple)

=4.6+( 1.25+0.75)

= 4.6 12

=6.6

3.4×7xl.5 (not easy)

=23.8x 1.5

=35.7

1.6x7.5x 1.25 (simple)

=(2x7.5)x(0.8x 1.25)

= 15x 1

= 15

0.8x0.25x0.4x 12.5 (simple)

=(0.8x 12.5)X(0.25x0.4)

= 10X0. 1

= 1