414242+425+2542
=
=
511 + 2542
Tìm x :
( 2/31*33 + 2/33*35 + ....... + 2/39*41 ) * 2542 - 2,04 : x = 19
\(\left(\frac{2}{31\times33}+\frac{2}{33\times35}+...+\frac{2}{39\times41}\right)\times2542-2,04:x=19\)
\(\Rightarrow\left(\frac{1}{31}-\frac{1}{33}+\frac{1}{33}-\frac{1}{35}+...+\frac{1}{39}-\frac{1}{41}\right)\times2542-2,04:x=19\)
\(\Rightarrow\left(\frac{1}{31}-\frac{1}{41}\right)\times2542-2,04:x=19\)
\(\Rightarrow\frac{10}{1271}\times2542-2,04:x=19\)
\(\Rightarrow20-2,04:x=19\)
\(\Rightarrow2,04:x=20-19\)
\(\Rightarrow2,04:x=1\)
\(\Rightarrow x=2,04:1\)
\(\Rightarrow x=2,04\)
Vậy x = 2,04
\(\left(\frac{2}{31\text{ x }33}+\frac{2}{33\text{ x }35}+...+\frac{2}{39\text{ x }41}\right)\text{ x }2542-2,04\text{ : }x=19\)
\(\left(\frac{1}{31}-\frac{1}{33}+\frac{1}{33}-\frac{1}{35}+...+\frac{1}{39}-\frac{1}{41}\right)\text{ x }2542-2,04\text{ : }x=1\)
\(\left(\frac{1}{31}-\frac{1}{41}\right)\text{ x }2542-2,04\text{ : }x=1\)
\(\frac{10}{1271}\text{ x }2542-2,04\text{ : }x=1\)
\(20-2,04\text{ : }x=1\)
\(2,04\text{ : }x=20-1\)
\(2,04\text{ : }x=19\)
\(x=2,04\text{ : }19\)
\(x=\frac{51}{475}\)
\(\left(\frac{2}{31\text{ x }33}+\frac{2}{33\text{ x }35}+...+\frac{2}{39\text{ x }41}\right)\text{ x }2542-2,04\text{ : }x=19\)
\(\left(\frac{1}{31}-\frac{1}{33}+\frac{1}{33}-\frac{1}{35}+...+\frac{1}{39}-\frac{1}{41}\right)\text{ x }2542-2,04\text{ : }x=19\)
\(\left(\frac{1}{31}-\frac{1}{41}\right)\text{ x }2542-2,04\text{ : }x=19\)
\(\frac{10}{1271}\text{ x }2542-2,04\text{ : }x=19\)
\(20-2,04\text{ : }x=19\)
\(2,04\text{ : }x=20-19\)
\(2,04\text{ : }x=1\)
\(x=2,04\text{ : }1\)
\(x=2,04\)
Tìm x, biết :
( 2 + 2 + ...... + 2 ) x 2542 - 2,04 : x =19
425 x 27 + 425 x 72 + 425 =............
Ta có:
425*27+425*72+425=425*(27+72+1)=425*100=42500
425x27+425x72+425
=425x27+425x72+425x1
=425x(27+72+1)
=425x100
=42500
425 x 27 + 425 x 72 + 425
= 425 x (27 + 72 + 1)
= 425 x 100
= 42500
TÍNH NHANH 425×32+69×425-425=? Làm nhanh cho em với ạ
425 x 32 + 69 x 425 - 425
= 425 x 32 + 69 x 425 - 425 x 1
= 425 x (32+69-1)
= 425 x 100
= 42500
250 : 0,1 = 425 : 0,01 =
250 : 10 = 425 : 100 =
250:0,1=2500
250:10=25
425:100=4,25
425:0,01=42500
250 : 0,1 =2500
250 : 10 = 25
425 : 0,01 = 42500
425 : 100 = 4,25.
+, 250:0,1=2500
+, 425:0,01=42500
+, 250:10=25
+, 425:100=4,25
Tinh nhanh
425*5847-125+1435*425
425 x 5847 - 125 + 1435 x 425
= 425 x ( 5847 + 1435) - 125
= 425 x 1982 - 125
= 842 225
425 x 5847 - 125 + 1435 x 425
= 425 x ( 5847 + 1435) - 125
= 425 x 1982 - 125
= 842 225
Tính hợp lí:
(-325). (425-27) - 425. (27-325)
\(\left(-325\right).\left(425-27\right)-425.\left(27-325\right)\)
\(=\text{ }\left[\left(-325\right).425-\left(-325\right).27\right]-\left(425.27-425.325\right)\)
\(=\left(-325\right).425-\left(-325\right).27-425.27+425.325\)
\(=\text{ }\left[\left(-325\right).425+425.325\right]-\text{ }\left[\left(-325\right).27+425.27\right]\)
\(=\text{ }\left\{425.\text{ }\left[\left(-325\right)+325\right]\right\}-\text{ }\left\{27.\text{ }\left[\left(-325+425\right)\right]\right\}\)
\(=\left(425.0\right)-\left(27.100\right)\)
\(=0-2700\)
\(=-2700\)
Số bị chia | 425 | 425 | 727 | 727 |
Số chia | 6 | 7 | 8 | 9 |
Thương | ||||
Dư |
Số bị chia | 425 | 425 | 727 | 727 |
Số chia | 6 | 7 | 8 | 9 |
Thương | 70 | 60 | 90 | 80 |
Dư | 5 | 5 | 7 | 7 |