\(8.19=8\left(10+9\right)\)
\(=8.10+8.9\)
\(=80+72\)
\(=152\)
\(65.98=65\left(90+8\right)\)
\(=65.90+65.8\)
\(=5850+520\)
\(=6370\)
8.19
=8.(20-1)
=8.20-8.1
=160-8
=152
65.98
=65.(100-2)
=65.100-65.2
=6500-130
=6370
8 x 19
= 8 x ( 20 - 1 )
= 8 x 20 - 8
= 160 - 8
= 152
65 x 98
= 65 x ( 100 - 2 )
= 65 x 100 - 130
= 6500 - 130
= 6370