Tính nhanh:
18 x 7 + 18 x 16 – 18 x 14 + 18
Tính nhanh:
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
= 12 x ( 11 + 13 ) + 14 x ( 13 + 15 ) + 16 x ( 15 + 17 ) + 18 x ( 17 + 19 ) + 20 x 21
= 12 x 24 + 14 x 28 + 16 x 32 + 18 x 36 + 420
= 288 + 392 + 512 + 648 + 420
= ( 288 + 392 ) + ( 512 + 648 ) + 420
= 680 + 1160 + 420
= 1840 + 420
= 2260
tk nha
=
Ta có:
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
= 12 x ( 11 + 13 ) + 14 x ( 13 + 15 ) + 16 x ( 15 + 17 ) + 18 x ( 17 + 19 ) + 20 x 21
= 12 x 24 + 14 x 28 + 16 x 32 + 18 x 36 + 420
= 288 + 392 + 512 + 648 + 420
= ( 288 + 392 ) + ( 512 + 648 ) + 420
= 680 + 1160 + 420
= 1840 + 420
= 2260
#Mạt Mạt#
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
= 12 x ( 11 + 13 ) + 14 x ( 13 + 15 ) + 16 x ( 15 + 17 ) + 18 x ( 17 + 19 ) + 20 x ( 19 + 21 )
= 12 x 24 + 14 x 28 + 16 x 32 + 18 x 36 + 20 x 40
= 288 + 392 + 512 + 648 + 800
= ( 288 + 392 ) + ( 512 + 648 ) + 800
= 680 + 1160 + 800
= 2640
18 x 7 + 18 x 16 - 18 x 14 + 18
mik vẫn cần gấp nha!!!!!!!!!!!!!!!!!
\(18\cdot7+18\cdot16-18\cdot14+18\)
\(=18\cdot\left(7+16-14+1\right)\)
\(=18\cdot10=180\)
\(\text{18 x 7 + 18 x 16 - 18 x 14 + 18}\)
\(=18\times\left(7+16-14+1\right)\)
\(=18\times10=180\)
18 x 7 + 18 x 16 - 18 x 14 + 18
= 18 x ( 7 + 16 - 14 + 1 )
= 18 x 10
= 180
tính nhanh
16 x 4 + 14 x 12 + 18 x 14
=(16+4)x(12+18)x14
=20x30x10x4
=500x10x4
=5000x4
=20 000
16 x 4 + 14 x 12 + 18 x 14
= 64 + 14 x (12 + 18)
= 64 + 14 x 30
= 64 + 420
= 484
tính nhanh 18 * 7 + 18 * 16 - 18 *14 + 18 =............................
giúp mk với
18 * 7 + 18 * 16 - 18 * 14 + 18
= 18 * (7 + 16 - 14 + 1)
= 18 * 8
= 144
\(18\times7+18\times16-18\times14+18\)
\(=18\times\left(7+16-14+1\right)\)
\(=18\times10\)
\(=180\)
Tính nhanh:
2020 x 14 + 4040 x 16 + 6060 x 18
2020 x 14 + 4040 x 16 + 6060 x 18
= 2020 x 14 + 2020 x 2 x 16 + 2020 x 3 x 18
= 2020 x 14 + 2020 x 32 + 2020 x 54
= 2020 x (14 + 32 + 54)
= 2020 x 100
= 202000
\(2020\times14+4040\times16+6060\times18\)
\(=2020\times14+2020\times2\times16+2020\times3\times18\)
\(=2020\times14+2020\times32+2020\times54\)
\(=2020\times\left(14+32+54\right)\)
\(=2020\times100\)
\(=202000\)
2. tính nhanh
6 x 7 x 8 x 9 x10/ 20 x 18 x 16 x 14 x12
46,7 x 99 cộng cộng 0,7
30240/967680
46,7x99+0,7=4624 nha bn
Tính Nhanh:
a) 3 x 7 x 9 / 7 x 5 x 3
b)6 x 8 x 11/ 16 x 24
c) 15 x 12 x 7/ 14 x 25 x 18
d) 118 x 13 - 13 x 18/ 79 + 21
e) 111 + 111 x 63 - 14 x 111
f) 126 - 27 + 74 - 73/ 21 x 11 + 39 x 21
G)146 x 21 + 146 - 46 x 22/ 88 x 25
18 x 7 + 18 x 6 - 18 x 14 + 18
giup minh nha
18 x 7 + 18 x 6 - 18 x 14 + 18
= 18 x (7 + 6) - 18 x 4 + 18
= 18 x 13 - 18 x 4 + 18
= 18 x (13 - 4 + 1)
= 18 x 10
= 180
20-18+18-16+16-14+14+1999
TÍNH NHANH
20-18+18-16+16-14+14+1999
=20-(18-18)-(16-16)-(14-14)+1999
=20+1999
=19+1+1999
=2000+19
=2019