a)`1,25 + 1,25 xx 2 + 7 xx 1,25=1,25 xx (1+2+7) = 1,25 xx 10 =12,5`
b)`3,62xx12–2xx0,362xx10=3,62 xx 12 -2 xx 3,62=3,62xx(12-2)=3,62xx10=36,2`
c)`12,35xx15–1,235xx10xx6+12,35=12,35xx15–12,35xx6+12,35=12,35xx(15-6+1)=12,35xx10=123,5`
d)`1,42 : 0,5 + 1,42 xx 8=1,42xx2+1,42xx8=1,42xx(2+8)=1,42xx10=14,2`