4/7 + 8 = 4/7+8/1 = 4/7+56/7 = 60/7
12 + 6/15 = 12/1 + 6/15 = 180/15 + 6/15 = 186/15
21 + 3/9 = 21/1 + 3/9 = 189/9 + 3/9 = 192/9
105 + 7/10 = 105/1 + 7/10 = 1050/10 + 7/10 = 1057/10
An doc ngay thu 1 duoc 1/5 cuon sach cong 10 trang , ngay 2 doc 4/9 so trang con lai cong 10 trang ,ngay 3 doc 2/7 so trang con lai cong 10 trang , ngay 4 doc 8/9 so trang con lai cong 10 trang .Hoi cuon sach day bao nhieu trang ?
tinh tong cac so chia het cho 4
tinh nhanh
3 cong 8 cong 13 cong ...cong 48
1 cong 3 cong 5 cong 7 cong ...2021
1 + 2 + 3 + 4 +5 + 6 = 7 +8 = 9 + 10 + 10000000
tìm trung binh cong
An doc ngay thu 1 duoc 1/5 cuon sach 10 trang ,ngay 2 doc 4/9 so trang con lai cong 10 trang ,ngay thu 3 doc 2/7 so trang con lai cong 10 trang ,ngay thu 4 doc 8/9 so trang con lai cong 10 trang . Hoi cuon sach co bao nhieu trang ?
tinh nhanh 4 phan 5 cong 2 phan 7 cong 11 phan 5 cong 12 phan 7 cong 1 phan 5
trung binh cong so bi cua 3 ban ha , hoa , hong la 33 bi neu ban ha bot 6 bi ban hong cong 7 bi hoa cong 8 bi thi so bi cua 3 ban = nhau.Tinh so bi cua 3 ban
Tinh nhanh
9/15 cong 16/20 cong 25/25 cong 30/36 cong 49/35 cong 64/40 cong 81/45 cong 100/50
3 Tinh
6/5-1/5 cong 1/4
1/2-1/4 cong 2/3
3/5 cong 4/9 -1/3
1 phan 6 cong 3 phan 4 cong 1 phan 8
