Môn Toán tính bằng hai cách: c1 3/4×2/5+3/4×2/7 c2 3/4×2/5+3/4×2/7 6 Tháng Chín, 2023 2 Comments tính bằng hai cách: c1 3/4×2/5+3/4×2/7 c2 3/4×2/5+3/4×2/7
a) C1 : 2/5 x 3/7 + 2/7 x 4/7 = 2/5 x (3/7 + 4/7) = 2/5 x 1 = 2/5 C2 : 2/5 x 3/7 + 2/5 x 4/7 = 6/35 + 8/35 = 2/5 b) (2/3 – 4/7) x 5/5 = 2/21 x 5/5 = 2/21 C2 : (2/3 – 4/7) x 5/5 = 2/3 x 1 – 4/7 x 1 = 2/3 – 4/7 = 2/21 c) 3/4 x 2/5 – 3/4 x 2/7 = 3/4 x (2/5 – 2/7) = 3/4 x 4/35 = 3/35 C2 : 3/4 x 2/5 – 3/4 x 2/7 = 3/10 – 3/14 = 3/35 Trả lời
Cách 1: 3/4×2/5+3/4×2/7 =3/10+3/14 =36/70=18/35 Cách 2: 3/4×2/5+3/4×2/7 =3/4×(2/5+2/7) =3/4×24/35 =18/35 Trả lời
