2.25×4= 1.01﹣0.91= 1÷0.01= ÷= ÷5.25=+6.25= 0.74×100= 742+258= 7×÷7×= 10﹣3.2﹣5.8=
简算.×3+×5+×10 999×7+111×7(+++)×2002.
简算 ①9﹣(3+0.4) ②1.8×+2.2×25% ③×[0.75﹣(﹣)].
.
=
1990×2.8+199×51+1.99×2100.