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15.2 Using hectares

15.2 Using hectares

You may need to measure areas of land. You use hectares to do this.
A hectare is the area of a square $eld, of side 100 metres.
A football pitch is about half a hectare.
!e abbreviation for hectare is ha.
You need to know this conversion. 1 hectare (ha) = 10 000 m 2

Worked example 15.2

2
2
a Copy and complete these statements. i 2.4 ha = m ii 125 000 m = ha
b A rectangular piece of land measures 850 m by 1.4 km.
Work out the area of the land. Give your answer in hectares.
a i 2.4 × 10 000 = 24 000 Multiply the number of hectares by 10 000 to convert to square metres.
2.4 ha = 24 000 m 2
ii 125 000 ÷ 10 000 = 12.5 Divide the number of square metres by 10 000 to convert to hectares.
125 000 m = 12.5 ha
2
b 1.4 km = 1400 m First, find the area of the land in square metres. Then change the answer
to hectares. Start by converting 1.4 km to metres.
area = 850 × 1400 Then work out the area of the land.
= 1 190 000 m This answer is in square metres.
2
1 190 000 ÷ 10 000 = 119 ha Divide by 10 000 to convert square metres into hectares.

) Exercise 15.2

1 Copy and complete these conversions.
a 3 ha = m b 4.6 ha = m c 0.8 ha = m 2
2
2
2
d 12.4 ha = m e 0.75 ha = m f 0.025 ha = m 2
2
2 Copy and complete these conversions.
a 50 000 m = ha b 89 000 m = ha c 240 000 m = ha
2
2
2
2
2
2
d 1500 m = ha e 900 m = ha f 1 265 000 m = ha
3 A rectangular piece of land measures 780 m by 550 m.
Work out the area of the land in: a square metres b hectares.
4 A farmer has an L-shaped field.
The dimensions of the field are shown in the diagram. 290 m
a Work out the area of the field, in hectares. 610 m
The farmer sells the field for $3950 per hectare. 390 m
b How much money does the farmer receive?
c Show how to use estimation to check your answer.
880 m
5 A company wants to build a theme park.
The diagram shows a plan of the land it wants to buy.
The company wants to pay no more than $16 million 4.8 km
for the land. 3.9 km
The price of the land is $5120 per hectare.
Can the company afford to buy the land?
Show all your working and use estimation to check your answer. 8.2 km
144 15 Area, perimeter and volume