A.可以假设1角和5角的各10枚,总钱数是6元,此时应减少5角的硬币数量,增加1角的硬币数量 |
B.调整时,减少1角的硬币,增加5角的硬币,总钱数会增加 |
C.1角的硬币每增加1枚,5角的硬币每减少1枚,总钱数就会减少0.4元 |
D.1角的硬币8枚,5角的硬币12枚,总钱数正好是6.8元。 |
同类型试题
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2