\(\dfrac{20}{15}+\dfrac{3}{15}=\dfrac{23}{15}\)
`4/3 + 3/15 = (4 xx 5)/(3 xx 5) + 3/15 = 20/15 + 3/15 = 23/15`
1.so sánh
1/2:2/3......2/3:1/2 4/7:2/5......4/7:3/5
4/15:4/7......2/5x10/3 5/6......15/18-11/18
2.viết số thích hợp vào ô trống
2/3=..../18 7/9=49/.... ..../5=18/15
..../3=10/15 5/9=..../45 49/56=7/....
6/8=42/.... 2/9=..../63 49/56=..../8
Số?
a) 1/4, 1/2, 3/4, 1, 5/4,...,...,...,...,...,...
b) 2/15, 1/3, 8/15, 11/15, 14/15,...,...,...,...
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
4 5. 4. 6.
--- + --- --- + ---
15 6. 5. 7
3. 4. 2. 5
--- + --- --- + ---
5. 20. 5. 12
15/4 + 3/2 = ? 15/4 - 3/2 = ?
15/4 nhân 3/2 = ? 15/4 : 3/2 = ?
a, 3/4- 2/5+ 5/12
b, 15/7-4/3- 2/9
c, 3/5+ 2/5x 4/5
d, 4/5 -(6/15 +1/5)
(2\15 -1\20 +3\15 -9\28+ 2\3) : 3\4
Tính nhanh (1+2+3+4+....+100)*(15*3-15*2*15)
Tỉ số giữa 15 năm và 1/4 thế kỉ là :
A. 5/3 B. 25/15 C. 3/4 D. 3/5
bài 1
4/7+4
3+6/11
3-5/7
21/9-2
15/24+2
63/45-20/25
3/4-2/8
6/7-5/8
37/45-5/9
46/39-11/13
5/12+3/4+1/3
1/2+3/7+11/14
7/10-(1/5+1/4)
15/4-2/3-3/4
5/6 + 5/8 + 3/4
12/15 + 3 + 3/5
4/3 x 7/8 x 5
8/9 x 6/5 : 3
7/12 + 5/8 x 4/3 - 3/4
(8/5 - 7/6) : 13/15 + 1/4
