1) (2525+25)-(2424+24) = 650-600 = 502) 2019-1918+1817-1716 = 380-342+306-272 = 723) 2625-2524+2423-2322 = 650-600+552-506 = 96
1) (2525+25)-(2424+24) = 650-600 = 50
2) 2019-1918+1817-1716 = 380-342+306-272 = 72
3) 2625-2524+2423-2322 = 650-600+552-506 = 96