25 + 75 + 55 + 56 + 85 + 100
tim cach tinh nhanh nhat cho cac cau hoi :
25*25
35*35
45*45
55*55
65*65
75*75
85*85
95*95
Bỏ ngoặc rồi tính :
a, - ( - 15 + 125 - 81 ) - ( - 85 + 75 - 19 + 100 )
b, ( 39 - 48 + 57 ) - ( - 61 + 52 + 157 )
c, ( -25 - 65 + 30 ) - ( 75 - 65 - 170 )
d, - ( - 45 - 135 + 29 ) + ( 55 - 35 - 71 )
a, -(-15+125-81)-(-85+75-19+100)
=-15-125+81-(-85)-75+19-100
=-140+81-(-85)-75+19-100
=-59-(-85)-75+19-100
=-16-75+19-100
=-91+19-100
=-72-100
=-172
15+25+35+45+55+65+75+85+95=
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95
= ( 15 + 85 ) + ( 25 + 75 ) + ( 35 + 65 ) + ( 45 + 55 ) + 95
= 100 + 100 + 100 + 100 + 95
= 495
Ngô Quang Ninh:
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95
= (15 + 85) + (25 + 75) + (35 + 65) + (45 + 55) + 95
= 100 + 100 + 100 + 100 + 95
= 495
Tham khảo nha!
Tính nhanh:15+25+35+45+55+65+75+85
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85
= (15 + 85) + (25 + 75) + (35 + 65) + (45 + 55)
= 100 + 100 + 100 + 100
= 400
15+25+35+45+55+65+75+85
=(15+85)+(25+75)+(35+65)+(45+55)
=100+100+100+100
=400
15+25+35+45+55+65+75+85
= ( 15+85) +( 25+75)+ ( 35+65)+( 45+55)
= 100+100+100+100=4 x 100 = 400
nhanh nhé
5+15+25+35+45+55+65+75+85+95=?????????
= ( 5 + 95 ) + ( 15 + 85 ) + ( 25 + 75 ) + ( 35 + 65 ) + ( 45 + 55 )
= 100 + 100 + 100 + 100 + 100
= 5 x 100
= 500
Điền (<; >; =).
75 203 ... 75 023 49 998 ... 50 002 81 102 ... 79 837
55 155 ... 55 155 100 000 ... 99 990 + 10 56 000 + 3000 ... 60 000
75 203 = 75 023 49 998 < 50 002 81 102 > 79 837
55 155 = 55 155
so sánh :
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95 và 500
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95 =495 vì 495 < 500 nên 15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95 < 500
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95 = 495
vậy 15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95 < 500
15 + 25 + 35 + 45 + 55 + 65 + 75 + 85 + 95 = 495.
Vậy 495 < 500
.Nhớ k cho mình nha!
\(85^2+75^2-65^2+55^2-45^2-35^2-25^2-15^2\)
Tính bằng cách hợp lý nhất
a, 2 x 26 x 5 b, 4 x 37 x 25 c, 25 x 5 x 4 x 27 x 2
d, 28 x 64 + 28 x 36 e, 769 x 85 - 769 x 75 f, 56 x 37 + 56 x 63
A, 2 x 26 x 5 =( 5 x 2) x 26
10 x 26
=260
b,4 x 37 x 25 =( 4 x 25) x 26
= 100 x 26
= 3700
c, 25 x 5 x 4 x 27 x 2 =( 25 x 4 ) x ( 2x 5) x 27
= 100 x 10 x 27
= 1000x 27
=27000
d,28 x 64 + 28 x 36 = 28 x ( 64 + 36 )
= 28 x 100
=2800
e, 769 x 85 - 769 x 75 = 769 x ( 85 - 75 )
=769 x 10
=7690
f, 56 x 37 + 56 x 63 = 56 x ( 37 + 63 )
= 56 x 100
=5600
a. = 26 x (2 x 5)
= 26 x 10 =260
b.=( 25x4) x37
=100 x37=3700
c.=(25x4) x(5x2) x27
=100 x10 x27
= 27000
d.=28 x( 64+36)
=28 x100
= 2800
e.=769 x( 85-75)
=769 x10 =7690
f. =56 x(37 +63)
=56 x100
= 5600