6.165 Найдите произведение: a) 90 000 ⋅ 40 000; б) 1500 ⋅ 900 000; в) 250 000 ⋅ 700 ⋅ 80; г) 15 000 ⋅ 40 000 ⋅ 60.

Решение:

• a) 90 000 ⋅ 40 000 = (9 ⋅ 4) ⋅ (10 000 ⋅ 10 000) = 36 ⋅ 10⁸ = 3 600 000 000
• б) 1500 ⋅ 900 000 = (15 ⋅ 9) ⋅ (100 ⋅ 100 000) = 135 ⋅ 10⁷ = 1 350 000 000
• в) 250 000 ⋅ 700 ⋅ 80 = (25 ⋅ 7 ⋅ 8) ⋅ (10 000 ⋅ 100 ⋅ 10) = (25 ⋅ 56) ⋅ 10⁷ = 1400 ⋅ 10⁷ = 14 000 000 000
• г) 15 000 ⋅ 40 000 ⋅ 60 = (15 ⋅ 4 ⋅ 6) ⋅ (1000 ⋅ 10 000 ⋅ 10) = 360 ⋅ 10⁸ = 36 000 000 000

Ответ: а) 3 600 000 000; б) 1 350 000 000; в) 14 000 000 000; г) 36 000 000 000