算一算。7+3= 6+4=10-2= 10-3=4+5= 5+5=10-9= 10-6=
5.09-(0.09+1.23) 9.36-(4.36-3.5)
7.5-2.45+7.5+2.45(-)×21+
2.5×(1.92÷0.3-5.9) 24.5-(7.58+)
45.55-(6.82+15.55) 34.52-17.87-12.23
(×+)÷÷[(+)×]