$a = 3$、$b = 2$ のとき、次の8つの式の値を求めます。 (1) $2a + 3b$ (2) $\frac{2a + 3b}{2}$ (3) $\frac{4a + 6b}{4}$ (4) $a + \frac{3}{2}b$ (5) $a - \frac{3}{2}b$ (6) $\frac{2a - 3b}{2}$ (7) $\frac{a - 3b}{2}$ (8) $\frac{4a - 6b}{4}$

1. 問題の内容

$a = 3$、$b = 2$ のとき、次の8つの式の値を求めます。

(1) $2a + 3b$

(2) $\frac{2a + 3b}{2}$

(3) $\frac{4a + 6b}{4}$

(4) $a + \frac{3}{2}b$

(5) $a - \frac{3}{2}b$

(6) $\frac{2a - 3b}{2}$

(7) $\frac{a - 3b}{2}$

(8) $\frac{4a - 6b}{4}$

2. 解き方の手順

それぞれの式に、$a = 3$、$b = 2$を代入して計算します。

(1) $2a + 3b = 2(3) + 3(2) = 6 + 6 = 12$

(2) $\frac{2a + 3b}{2} = \frac{2(3) + 3(2)}{2} = \frac{6 + 6}{2} = \frac{12}{2} = 6$

(3) $\frac{4a + 6b}{4} = \frac{4(3) + 6(2)}{4} = \frac{12 + 12}{4} = \frac{24}{4} = 6$

(4) $a + \frac{3}{2}b = 3 + \frac{3}{2}(2) = 3 + 3 = 6$

(5) $a - \frac{3}{2}b = 3 - \frac{3}{2}(2) = 3 - 3 = 0$

(6) $\frac{2a - 3b}{2} = \frac{2(3) - 3(2)}{2} = \frac{6 - 6}{2} = \frac{0}{2} = 0$

(7) $\frac{a - 3b}{2} = \frac{3 - 3(2)}{2} = \frac{3 - 6}{2} = \frac{-3}{2} = -\frac{3}{2}$

(8) $\frac{4a - 6b}{4} = \frac{4(3) - 6(2)}{4} = \frac{12 - 12}{4} = \frac{0}{4} = 0$

3. 最終的な答え

(1) 12

(2) 6

(3) 6

(4) 6

(5) 0

(6) 0

(7) $-\frac{3}{2}$

(8) 0