maths

Q: a distance of 2 km is represented by 1 cm on the map.

1]a pool has an area of 2 cm次方on the map. find it's actual area.

1cm=2km
2cm次方=(2×2)(2×2)km次方
2cm次方=16km次方


Q: 3.33333 :9.9999999
= 1 : 3.00000297
= 1 : 3 (corr to the nearest integer.)

Q: the scale of map = 1:100000. if a road is 5 cm on map .find its actual length
1:100000
5:100000×5
5:500000
the actual length is: 500000cm=5km


Q: scale in map 1 :5000. a park is measured 4cm *3cm on map. find actual area
4cm=5000×4=20000cm=0.2km
3cm=5000×3=15000cm=0.15km

the actual area = 0.2×0.15=0.03km square.