ІІ ЧАСТИНА. I. Тисяча » 257-258
258. 690 + 10 = 700; 420 + 80 = 500; 864 – 64 = 800; 999 – 888 = 111; 650 + 150 = 800; 540 – 30 = 510.
258. 690 + 10 = 700; 420 + 80 = 500; 864 – 64 = 800; 999 – 888 = 111; 650 + 150 = 800; 540 – 30 = 510.