小学五年级求面积周长题

面积：7×10.5=73.5 cm
10.5-3×2-2
=10.5-6-2
=4.5-2
=2.5 cm
2.5×2.5=6.25
2.5×2=5
73.5-6.25-5
=67.25-5
=62.25c㎡

周长：（10.5+7）×2
=17.5×2
=35cm
35+2.5×3
=35+7.5
=42.5cm
答：这个图形的周长是42.5c㎡ ,面积是62.25c㎡

7×10.5=73.5
10.5-3×2-2
=10.5-6-2
=4.5-2
=2.5
2.5×2.5=6.25
2.5×2=5
73.5-6.25-5
=67.25-5
=62.25C㎡

（10.5+7）×2
=17.5×2
=35
35+2.5×3
=35+7.5
=42.5