gọi số lớn là a,số bé là b
ta có:40%=2/5
(a+b)x2/5=b
ax2/5+bx2/5=b
ax2/5=bx1-bx2/5
ax2/5=bx(1-2/5)
ax2/5=bx3/5
ax2/5=bx2/5+bx1/5
ax2/5-bx2/5=bx1/5
(a-b)x2/5=bx1/5
19,5x2/5=bx1/5
7,8=bx1/5
b=7,8:1/5
b=39
a=19,5+39
a=58,5
TICK mình nha!!Mình là người giải chi tiết và đúng nhất!!
Bai 1 : Tong cua hai so la 2000. Neu so hang thu nhat them 135 don vi va so hang thu hai bot 531 don vi thi duoc tong moi la bao nhieu?
Bai 2 : Tim tong hai so biet rang neu so hang thu nhat bot di 246 don vi va so hang thu hai them 642 don vi thi duoc tong moi bang 2010.
Bai 3 : Hieu cua hai so la 1000. Neu so lon them 235 don vi va so be bot 200 don vi thi duoc hieu moi la bao nhieu?
Bai 4 : Hieu cua hai so bang 1234. Neu so lon bot 234 don vi va so be them 456 don vi thi duoc hieu moi la bao nhieu?
Bai 5 ; Tim hieu cua hai so, biet rang so lon va so be cung bot di 100 don vi thi duoc hieu moi la 1000.
Biet hieu cua 2 so bang 1/5 tong cua 2 so do va so be lon hon hieu cua 2 so do la 19,5
tong cua 2 so tu nhien la 630.tim so be biet neu bót so be di 19 don vi va them vao so lon 19 don vi thi so be bang 3/4 so lon
cho 2 so co tong bang 702 biet neu them vao so be 11 don vi va so lon 15 don vi thi duoc 2 so moi co ti so la 2,25 tim so lon
trong 1 phep chia co so tu nhien co thuong 4 du 7 va tong cua 2 so la 177 tim so bi chia va so chia
tim 2 so biet tong cua so tru va so bi tru va hieu bang 1470 so tru be hon hieu la 243
tim 2 so tu nhien co hieu la 45 biet rang neu them vao so lon 15 don vi va giam so be di 8 don vi thi duoc 2 so moi co thuong bang 5
Hieu cua 2 so la 41 biet neu giam so be di 19 lan va them vao so lon 12 don vi thi so be
bang 3/5 so lon tim hai so do
1. trong 1 phep chia co thuong la 3 va so du la 24 va biet hieu giua so bi chia va so chia la 218. tim so bi chia va so chia
2. biet trung binh cong hai so lon hon so be 24 don vi . biet so lon hon so be 24 don vi. biet so lon la 68 . tim so be
TRA LOI CAU HOI SAU:
cau1:1/3 cua 186 bang
cau2:5/4cua 2012 bang
cau3:3/4 cua 192 bang
cau4:hieu hai so bang 246 so be bang 3/5 so lon vay so lon la
cau5:tong hai so bang 222 biet rang neu cung them moi so 9 don vi thi so lon gap doi so be tim so lon
cau6:cho hinh chu nhat co chu vi bang 104cm biet neu giam chieu dai di 2cm va tang chieu rong len 2cm thi no cho thanh hinh vuong so do chieu dai hinh chu nhat la
cau7:tong 2 so bang 260 biet neu cung bot moi so di 6 don vi thi so lon gap 3 lan so be vay so be la
