+) A = ( 1,11 + 0,19 - 2,6 ) : ( 2,06 + 0,54 ) - ( \(\frac{1}{2}\) + \(\frac{1}{3}\) ) : 2
+) Tìm x :
a, (1,16 - x ) . 2,25 / 10 \(\frac{5}{9}\) - 7\(\frac{1}{4}\) . 2\(\frac{2}{11}\) = 75%
b) x + 25% .x = -1,25
c) x - 75% x = \(\frac{1}{4}\)
+) Tính nhanh nếu có thể :
a) 1\(\frac{1}{2}\) - 3\(\frac{3}{4}\) b) -8\(\frac{1}{6}\) - 7\(\frac{3}{2}\) c) 0,15 - 4,8 + 1,3 d) ( 2\(\frac{1}{3}\) + 3,5 ) : (-4\(\frac{1}{6}\) + 3\(\frac{1}{7}\) ) + 7,5
e) 11\(\frac{1}{4}\) + (2\(\frac{5}{7}\) + 5\(\frac{1}{4}\) ) f) \(\frac{4}{9}\) : ( \(\frac{1}{-7}\) + 6\(\frac{5}{9}\) :(-\(\frac{1}{7}\))
Bài 2:
b: x+25%x=-1,25
=>1,25x=-1,25
hay x=-1
c: x-75%x=1/4
=>1/4x=1/4
hay x=1
Bài 2:
a: =3/2-11/4=6/4-11/4=-5/4
b: =-49/6-17/2=-49/6-51/6=-100/6=-50/3