ta có pt: 25%x+50%=45
<=> 75%x=45
=> x=45/75%=60
vậy x =60
25%x + 50%x = 45
75%x = 45
x = \(45:\frac{100}{75}\)
x = \(\frac{45.100}{75}\)
x = \(\frac{4500}{75}\)
\(x=60\)
mot so le co 3 chu so biet rang so do chia cho 5 du 4 va neu chuyen chu so hang do len dau thi ta duoc 1 so moi bang ba lan so ban dau cong them voi 3 . tim so do
Tim phan so toi gian biet khi cong ca tu va mau cua phan so ay voi mau so cua no ta duoc mot phan so moi lon gap 3 lan phan so ban dau.
GIUP MINH GAP NHOA!!!!!!!!!!!!!!!
Ai biet thi giup minh voi nha
Cau hoi la :tim so tu nhien co 5 chu so biet rang neu viet them chu so 2 vao dang sau so do thi duoc so lon gap 3 lan so co duoc bang cach viet them chu so 2 vao dang truoc so do
[ ai lam dung minh se tich cho]
tim cac so nguyen x biet 25-(30+x)
tim mot so co 4 chu so biet rang khi viet them chu so 3 vao ben trai so do thi duoc so moi gap 7 lan so phai tim
GIUP EM NHA MOI NGUOI !!
Cau 1 : Trong mot cuoc thi co 20 cau hoi , moi cau tra loi dung duoc 10 diem , con sai thi tru 3 diem . 1 hs dat duoc 148 diem . Hoi ban ay tra loi duoc bao nhieu cau dung , bao nhieu cau sai Cau 2 : Tim so bi chia , so chia cua mot phep chia biet rangthuong = 3 va so du = 2 . Tong cua so bi chia , so chia , so du = 76 Cau 3 : Tich cua 2 so la 1692 , neu them 4 dv vao mot thua so thi tich moi la 1880 . Tim 2 so do Co ai biet lam thi chi minh voi 
tim so tu nhien co 3 chu so biet rang neu tang moi chu so cua no len n don vi thi ta duoc mot so co 3 chu so gap n lan so da cho
Trung binh cong cua 3 so la so be nhat co 3 chu so khac nhau biet so thu 2 bang trung binh cong cua 2 so con lai .so thu 3 hon so thu nhat 14.tim 3 so do
tim so co 2 chu so biet rang neu viet xen chu so 0 vao gia 2 chu so cua nothi ta duoc so moi bang 7 lan so phai tim.
