luas bangun gabungan disamping adalah

(½.15.20) + (25.20) + (½ . 3,14 . 10²)
= (150) + (500) + (157)
= 807cm²

L1= 1/2xπxrxr
= 1/2 x 22/7 x 20 x 20 = 30800 cm
L2 = 1/2 x ( a + b) x t
= 1/2 x ( 40 + 25 ) x 20
= 1/2 x 65 x 20
= 650 cm
L1 + L2 = 30800 cm + 650 cm = 31.450 cm²
maaf kalo salah