Volume Bangun Ruang

3. V = V kubus + V balok

= s³ + plt

= 12³ + (20 x 12 x 12)

= 1728 + 2880

= 4608 cm³

4. V = V prisma segitiga + V balok

= (2 x 1/2 at x t prisma) + plt

= (at x t prisma) + plt

= (8 x 8 x 12) + (16 x 12 x 8)

= 768 + 1536

= 2304 cm³

5. jari-jari (r) = 27 - 20 = 7 cm

V = V setengah bola + V tabung

= 2/3 πr² + πr²t

= (2/3 x 22/7 x 7²) + (22/7 x 7² x 20)

= (44/3 x 7) + (22 x 7 x 20)

= 102,67 + 3080

= 3182,67 cm³

6. t limas = √(18² - 9²) = √(324 - 81) = √243 = 9√3 = 15,59 cm

V = V limas segiempat + V kubus

= 1/3 x s² x t limas + s³

= 1/3 x 18² x 15,59 + 18³

= 1/3 x 324 x 15,59 + 5832

= 1683,72 + 5832

= 7515,72 cm³

7. t kerucut = √(s² - r²) = √(25² - 7²) = √(625 - 49) = √576 = 24 cm

V = 2 x V kerucut + V tabung

= 2 x 1/3 πr²t + πr²t

= (2 x 1/3 x 22/7 x 7² x 24) + (22/7 x 7² x 20)

= (44 x 7 x 8) + (22 x 7 x 20)

= 2464 + 3080

= 5544 cm³

8. V = V balok 1 + V balok 2

= plt + plt

= (18 x 5 x 6) + (12 x 5 x 5)

= 540 + 300

= 840 cm³