\(\frac{1}{1}\cdot2=2\)
\(\frac{1}{2}\cdot3=\frac{3}{2}\)
\(\frac{1}{1}\cdot2=2\)
\(\frac{1}{2}\cdot3=\frac{3}{2}\)
bai 1
cho tong : S = 5 + 8 + 11 +14 = ....
a) tim so hang thu 100 cua tong
b) tinh tong 100 so hang dau tien
bai 2
cho tong : S = 7 + 12 + 17 + 22 + .......
a) tim so hang thu 50 cua tong
b) tinh tong 50 so hang dau tien
bai 3
tinh tong cua tat ca cac so hang tu nhien x , biet x la so tu nhien co 2 chu so va 12 < x <91
ban nao lam ho minh 3 bai tren voi ma ban nao nao lam ra dau tien minh se tich ngay va lun
Cho tong S =7+12+17+22+...
a,Tim so hang thu 50
b,Tinh tong cua 50 so hang dau tien
cho day so 2.4,4.6,6.8,.....
tim so hang thu 50 cua day
tinh tong cua 50 so hang dau tien
Cho day so 2*4;4*6;6*8;8*10;....
a,Tim so hang thu 50 cua day so tren
b, Tinh tong cua 50 so hang dau tien cua day so
tinh tong cac so nguyen a sao cho:
-50<a<hoac bang 50
-100 nho hon hoac bang a va a nho hon 100
(1/1;2/1;3/1;2/2;1/3;4/1;3/2;2/3;1/4)
Tim quy tac va viet them 5 so nua
50/31 la so thu may cua day do
50/31la so thuoc nhom bao nhieu va la so hang thu bao nhieu cua day va cua nhom
1 nguoi mang 150 qua camdi ban. Lan 1 ban dc 40% tong so cam. So cam lan1 bang 3/2 so cam ban lan thu 2, lan thu 3 thi nguoi do ban het. Tinh ti so% so cam ban lan1 va lan3
TBC 3 so la ̀50. Biet so thu nhat kem so thu hai 22 don vi va hon so thu ba 7 don vi. Tim 3 so do.
tong 3 so -84 Biet rang ti so giuaso thu nhat va so thu 2 =1/2 va ti so giua so thu 2 va 3 cung = 1/2 . tim cac so do