a,
= 7,9 nhân ( 8,3 + 1,7 )
=7,9 nhân 10
=79
b,........
A) 8,3.7,9+7,9.1,7
=7,9.(8,3+1,7)
=7,9.10=79
B) (8,27+7,16)-(7,27+6,16+8,33)
=8,27+7,16-7,27-6,16-8,33
=(8,27-7,27)+(7,16-6,16)+8,
a) 8,3x7,9+7,9x1,7
=7,9x(8,3+1,7)
=7,9x10
=79
b) (8,27+7,16)-(7,27+6,16+8,33)
= 8,27+7,16-7,27-6,16-8,33
=(8,27-7,27)+(7,16-6,16)-8,33
= 1+1-8,33
=2-8,33
=-6,33