24. Pada gambar di samping,

p = 32 cm

l = 18 cm

t = 12 cm

t1 = V[t^2 + (1/2 × p)^2]

t1 = V[12^2 + (1/2 × 32)^2]

t1 = V[12^2 + 16^2]

t1 = V[144 + 256]

t1 = V400

t1 = 20 cm

t2 = V[t^2 + (1/2 × l)^2]

t2 = V[12^2 + (1/2 × 18)^2]

t2 = V[12^2 + 9^2]

t2 = V[144 + 81]

t2 = V225

t2 = 15 cm

L permukaan limas

= L alas + 2L sisi tegak 1 + 2L sisi tegak 2

= (p × l) + (2 × 1/2 × p × t2) + (2 × 1/2 × l × t1)

= (32 × 18) + (2 × 1/2 × 32 × 15) + (2 × 1/2 × 18 × 20)

= 576 + 480 + 360

= 1416 cm^2