Photo AI

A rectangular sportsground has been drawn to scale on a 1-cm grid as shown - HSC - SSCE Mathematics Standard - Question 25 - 2021 - Paper 1

Question icon

Question 25

A-rectangular-sportsground-has-been-drawn-to-scale-on-a-1-cm-grid-as-shown-HSC-SSCE Mathematics Standard-Question 25-2021-Paper 1.png

A rectangular sportsground has been drawn to scale on a 1-cm grid as shown. The scale used is 1:3000. Kerry took 12 minutes to walk around the perimeter of this spo... show full transcript

Worked Solution & Example Answer:A rectangular sportsground has been drawn to scale on a 1-cm grid as shown - HSC - SSCE Mathematics Standard - Question 25 - 2021 - Paper 1

Step 1

Calculate the perimeter of the diagram

96%

114 rated

Answer

The perimeter can be calculated using the formula for the perimeter of a rectangle:

P=2imes(length+width)P = 2 imes (length + width)

From the diagram, the length is 8 cm and the width is 5 cm. Thus,

P=2imes(8+5)=2imes13=26extcmP = 2 imes (8 + 5) = 2 imes 13 = 26 ext{ cm}

Step 2

Convert the perimeter to actual distance

99%

104 rated

Answer

Using the scale of 1 cm = 3000 cm (or 30 m), the actual perimeter in metres is:

extActualperimeter=26extcmimes3000=78000extcm=780extm ext{Actual perimeter} = 26 ext{ cm} imes 3000 = 78000 ext{ cm} = 780 ext{ m}

Step 3

Calculate Kerry's speed

96%

101 rated

Answer

Kerry took 12 minutes to walk around the perimeter. To find the speed in km/h, first convert the distance to km:

780extm=0.78extkm780 ext{ m} = 0.78 ext{ km}

Now, speed is calculated as:

extSpeed=DistanceTime=0.78extkm1260exthours=0.78extkm0.2exthours=3.9extkm/h ext{Speed} = \frac{Distance}{Time} = \frac{0.78 ext{ km}}{\frac{12}{60} ext{ hours}} = \frac{0.78 ext{ km}}{0.2 ext{ hours}} = 3.9 ext{ km/h}

Join the SSCE students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;