80% X( 1- 10%)= 144
X=200
Answer; Original price 200 yuan.
2. solution: the degree of this angle is x, which can be obtained from the problem:
90-X+20=( 180-X)/3
X=75
The degree of this angle is 75 degrees.
3. Solution: The price of each piece is X yuan, which can be obtained from the question:
0.9X=2 1 ×( 1+20%)
X=28
The price of each piece is 28 yuan.
4. Solution: ∫| a-2b |+(b-3c)2 (power) =0.
∴ a-2b=0，b-3c=0，
∴a=2b，b=3c
∴a+b-2c=2×3c+3c-2c=7c
5. Solution: A-(-3x+5)+x? -x-7=5x？ -3x
A=4x？ -6x+ 12
6. Solution: 2n+ 1
7. Solution:
8. Solution: Two shepherds each have X and Y sheep, which can be obtained from the question:
y+ 1 = 2(x- 1)x+ 1 = y- 1
∴x=5。 y=7
A: A shepherd boy has five sheep, and B shepherd boy has seven sheep.
9. Solution:
10, solution: There are x oranges in her basket, which can be obtained from the question:
X- 1/2X- 1- 1/2(X- 1/2X- 1)- 1/2[X- 1/2X- 1- 1/2(X- 1/2X- 1)- 1]
0. 125X=3.75
X=30
There used to be 30 oranges in her basket.