(18x123+9x4567x2+3x5310x6):(1+4+7+10....+55+58-490) =?
1. Tính nhanh
a) 2006x125+1000 phần 126x2005-888
b) 18x123+9x4567x2+3x5310x6 phan 1+4+7+10+...+49+52+55+58-410
18x123+9x4567x2+5310x6
1+4+7+10+...+49+52+55+58-410
\(\frac{18\cdot123+9\cdot4567\cdot2+5310\cdot6}{1+4+7...+55+58-410}\)
\(=\frac{18\cdot123+18\cdot4567+1770\cdot18}{\left(58+1\right)\cdot\left[\left(58-1\right):3+1\right]:2-410}\)
\(=\frac{18\left(123+4567+1770\right)}{590-410}\)
\(=\frac{18\cdot6460}{180}\)
\(=646\)
Tính Nhanh ( chữ x trog bài b là dấu nhấn )
a) \(\dfrac{2+4+6+8+...+82+84}{4+7+10+13+...+130+133}\)
b) \(\dfrac{18x123+9x4567x2+3x5310x6}{\left(2+4+6+...+20+22\right)+48}\)
a: Đặt A=2+4+...+82+84
Số số hạng là (84-2):2+1=42(số)
Tổng là (84+2)*42/2=1806
Đặt B=4+7+...+130+133
Số số hạng là (133-4):3+1=44(số)
Tổng là (133+4)*44/2=3014
=>C=1806/3014=903/1507
b: \(=\dfrac{18\left(123+4567+5310\right)}{132+48}=\dfrac{18\cdot10000}{180}=1000\)
18x123+9x4567x2+3x5310x6
[2+4+6+8+...+18+20+22]+48
18 x 123 + 9 x 4567 x 2 + 3 x 5310 x 6
= 18 x 123 + 18 x 4567 + 18 x 5310
= 18 x (123 + 4567 + 5310)
= 18 x 10000
= 180000
18.123+9.4567.2+3.5310.6
=18.123+9.2.4567+3.6.5310
=18.123+18.4567+18.5310
=18.(123+4567+5310)
=18.10000=180000
DẤU CHẤM LÀ NHAN NHÉ !
( 2+4+6+...+18+20+22) + 48
= (22+2).[(22-2):2+1] : 2 + 48
= 132 + 48
= 180
phần a bn lm như mấy bn kia nha\
tính nhanh
a,27x121-87x27+73x34
b,48x19+134x52+48x115
c,65+891+135+909/731-47+69-253
d,18x123+9x4576x2+3x5310x6/1+4+7+.............+55+58-410
a) 27.121-87.27+73.34
=27.(121-87)+73.34
=27.34+73.34
=34(27+73)
=34.100
=3400
b) 48.19+134.52+48.115
=48.19+48.115+134.52
=48(19+115)+134.52
=48.134+134.52
=134(48+52)
=134.100
=13400
c) 65+891+135+909/731-47+69-253
VT:(65+135)+(891+909)
=200+1800
=2000
VP:(731+69)-(253+47)
=800-300
=500
2000/500=4
d)18.123+9.4576.2+3.5310.6/1+4+7+..+55+58-410
VT:18.123+18.4567+18.5310
=18(123+4567+5310)
=18.10009
=18(10000+9)
=180000
VP:Tổng : 1+4+7+...+55+58
Có số số hạng là :
(58-1):3+1=20( số )
Tổng bằng : (58+1).20:2=590
590-410=180
180000:180=1000
Mình chữa câu d tí 9.4576.2 là sai ;;; 9.4567.2 mới đúng
18x123+9x4567+5310x6/1+4+7+10+...+49+52+55+58-410
18x123+2x4567x9+6x5310
-----------------------------------------------------
1+4+7+10+...+49+52+55+58-410
a,2006x2005-1/2004x2006+2005 b,45x45+45x55/1+3+5+.......+19 c,7256x4375-725/3650+4375x7255
d,35x12+65x13 g,18x123+9x4567x2+3x5310x6
a,2006x2005-1/2004x2006+2005 b,45x45+45x55/1+3+5+.......+19 c,7256x4375-725/3650+4375x7255
d,35x12+65x13 g,18x123+9x4567x2+3x5310x6