(1)3260-997 =3260-(1000-3) =3260-1000+3 =2260+3 =2263; (2)360÷45 =360÷9÷5 =40÷5 =8; (3)88×25 =22×4×25 =22×(4×25) =22×100 =2200; (4)536+298 =536+(300-2) =536+300-2 =836-2 =834.