panjang 27cm,lebar 1cm. berapa mm keliling dan luas persegi panjang

Keliling = 2×(p+l)
= 2×(27cm+1cm)
= 2×(270mm+10mm)
= 2×280mm
= 560 mm

Luas = p×l
= 27cm×1cm
= 270mm×10mm
= 2700 mm2

maaf kalo salah

K = 2p + 2l
   = 2.27 + 2.1
   = 54 + 2
   = 56 cm
   = 56 x 10 = 560 mm

L = pxl
   = 27 x 1
   = 27 cm²
   = 27 x 100 = 2700 mm²