75% = 3/4
800 · 3/4 = 600 - 75% от 800
700 : 100 · 34 = 238 - 34% от 700
69 : 9 = 7 ( 6 остаток)
Проверка:
7 * 9 + 6 = 63 + 6 = 69
Http://ru.static.z-dn.net/files/d81/9e48342d1b01618f0a8c443a3827fcee.jpg
посмотри это
8, 246...
........................
А)
2 1/4 : 3 * (3 - 1 2/3) + 5/6 =
= 9/4 : 3 * (9/3 - 5/3) + 5/6 =
= 9/4 * 1/3 * 4/3 + 5/6 =
= 1 + 5/6 = 1 5/6,
Б)
1/2 + 10 : (5 - 1 1/4) * 1 4/5 =
= 1/2 + 10 : (20/4 - 5/4) * 9/5 =
= 1/2 + 10 : 15/4 * 9/5 =
= 1/2 + 10 * 4/15 * 9/5 =
= 1/2 + 24/5 =
= 5/10 + 48/10 =
= 53/10 = 5 3/10