có ai chả lời được không

(8 + 9) x 9 - 23

= 17 x 9 - 13

= 153 - 13

= 140

B1

a) 17 b) 6 c) 112 d)9687

B2

100-x=33

x=100-33

x= 67

Ko bít

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Trả lời :

a)\(\frac{8}{3}+\frac{8}{9}\)

\(=\frac{72}{27}+\frac{24}{27}\)

\(=\frac{96}{27}\)

\(=\frac{32}{9}\)

b)\(988888+2000=9908888\)

Hok_tốt

#Thiên_Hy

\(\frac{8}{3}+\frac{8}{9}=\frac{32}{9}\)

988888 + 2000 =990888

.

1 - 2 + 3 - 4 + 5 - 6 + 7 - 8 + 9

= (9 - 8) + (7 - 6) + (5 - 4) + (3 - 2) + 1

= 1 + 1 + 1 + 1 + 1

= 1 x 5

= 5

5

bằng 115

= 115

C1: \(\left(\frac{3}{5}+\frac{4}{9}\right)\cdot\frac{3}{8}=\frac{47}{45}\cdot\frac{3}{8}=\frac{141}{360}=\frac{47}{120}\)

C2: \(\left(\frac{3}{5}+\frac{4}{9}\right)\cdot\frac{3}{8}=\frac{3}{5}\cdot\frac{3}{8}+\frac{4}{9}\cdot\frac{3}{8}=\frac{9}{40}+\frac{12}{72}=\frac{47}{120}\)

C1: ( \(\frac{3}{5}+\frac{4}{9}\) ) * \(\frac{3}{8}\) 

= \(\frac{47}{45}\) * \(\frac{3}{8}\) = \(\frac{47}{120}\) 

C2: Đề

= 3/5 * 3/8 + 4/9 * 3/8

= 9/40 + 1/6

= 47/120

9 x 5 = 45

9 x 6 = 54

9 x 7 = 63

9 x 8 = 72

9 x 9 = 81

45

54

63

91

10+9-8+7-6+5-4+3-2+1-0

= 10 +[(9 - 8) + (7 - 6) + (5 - 4) + (3 - 2) + (1 - 0)]

= 10 + [1 + 1 + 1 + 1 + 1]

= 10 + 1 x 5

= 10 + 5

= 15

15

5+6+7+8+9

=35

5+6+7+8+9+10

=45

52 + 8 x 5 + 9 = 52 + 40 + 9

                     = 92 + 9

                     = 101

\(=52+40+9\)

\(=92+9\)

\(=101\)