1/2+1/4+1/8+1/10+1/16+1/32+1/64+1/128
=1-1/2+1/2-1/4+1/4-1/6+1/6-1/8+1/8-1/16+1/16-1/32+1/32-1/64+1/64-1/128+1/128
=1-1/128
=127/128
#Sagittarius#
tinh tong sau 1 cong 1tren 2 cong 1 tren 3 cong 1 phan 4
khi cong 1 so tu nhien voi 1 so thap phan ma phan thap phan co 2 chu so ban hoa da bo quen dau phay o phan thap phan va dat tinh nhu cong so tu nhien nen duoc ket qua la 2015 tim so thap phan biet tong dung la 177.56
1 .trung binh cong cua hai phan so la 5/12 .neu tang phan so thu nhat gap 2 lan thi trung binh cong cua chung bang 2/3 .tim hai phan so do .
2.trung binh cong cua ba phan so la 13 /36 .neu tang phan so thu nhat gap 2 lan thi trung binh cong cua chung bang 19/36 ,cho biet phan so thu hai lon hon phan so thu ba 1 /12. tim ba phan so do .
giai giup toi : khi cong 1 so thap phan, mot ban hoc sinh da quen danh dau phay o so thap phan va dat phep tinh cong nhu so tu nhien nen tong la 404. tong dung la 134,72. tim so tu nhien va so thap phan do, biet so tu nhien co 3 chu so va so thap phan co phan nguyen gom 1 chu so ?
Tong 1 so thap phan va 1 so TN la 22,72.Khi cong hai so do , mot ban quen mat dau phay o so thap phan va cong nhu la cong hai so TN nen duocj ket qua la 490 . Tim so TN va so thap phan da cho.
tong cua 1 so tu nhien va 1 so thap phan la 62,42.khi cong hai so nay mot ban quen mat dau phay o so thap phan va dat tinh cong nhu so tu nhien nen ket qua la 3569.tim so tu nhien va so thap phan da cho
tim 1 phan so biet neu giu nguyen mau so cong tu so voi 4 thi duoc phan so moi bang 1 neu giu nguyen tu so cong mau so voi 1 thi duoc phan so moi bang 1/2
khi cong voi 1 so thap phan co 2 chu so o phan thap phan, do so suat ,1 hoc sinh da bo quen dau phay cua so thap phan va dat phep tinh nhu cong so tu nhien, vi vay ket qua cua phep tinh da tang them 242,55 don vi. tim so thap phan do
cho a bang 8 phan 11 nhan 13 cong 8 phan 13 nhan 15 cong... cong 8 phan 19 nhan 21 va b bang 36 phan 231
