Some problems in Mathematics in grade two of junior high school 1. Without changing the value of the fraction, change the coefficients in the numerator and denominator of the following formulas into integers (1) (5 / 6 x) + y (2 / 3 x) minus (2 / 3 y) (2) (0.3A) - 2b of (0.7b) Calculate one question: - 2 ≤ one third (1-2x) < 1 | Math enthusiast | Mathematical art

Some problems in Mathematics in grade two of junior high school 1. Without changing the value of the fraction, change the coefficients in the numerator and denominator of the following formulas into integers (1) (5 / 6 x) + y (2 / 3 x) minus (2 / 3 y) (2) (0.3A) - 2b of (0.7b) Calculate one question: - 2 ≤ one third (1-2x) < 1

(1) 5X/6+(2X/3)/y-2y/3
Multiply by 6, original = 5x + 4x / y-4y
(2) -10a+0.7b/0.3a-2b
Multiply by 10, original = - 100A + 7b / 3a-20b
Calculation question: - 2 ≤ (1-2x) / 3 ＜ 1
(1-2X )/3≥ -2 (1-2X)/3＜1
1-2X ≥ -6 1-2X＜3
-2X ≥-7 -2X＜2
X ≤ 7/2 X>-1
So the solution of the inequality is - 1 < x ≤ 7 / 2

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