Photo AI

Ray is fitting draught excluders around the outside of one of his windows - Junior Cycle Mathematics - Question 10 - 2014

Question icon

Question 10

Ray-is-fitting-draught-excluders-around-the-outside-of-one-of-his-windows-Junior Cycle Mathematics-Question 10-2014.png

Ray is fitting draught excluders around the outside of one of his windows. To do this, he needs to find the perimeter of the window. The window is in the shape of a ... show full transcript

Worked Solution & Example Answer:Ray is fitting draught excluders around the outside of one of his windows - Junior Cycle Mathematics - Question 10 - 2014

Step 1

What is the radius of the semicircle?

96%

114 rated

Answer

The radius of the semicircle is given by half of the diameter. Since the diameter is stated as 1.2 metres, we can calculate the radius as follows:

ext{Radius} = rac{ ext{Diameter}}{2} = rac{1.2}{2} = 0.6 ext{ m}

Thus, the radius of the semicircle is 0.6 metres.

Step 2

Find the length of the semicircle.

99%

104 rated

Answer

To find the length (circumference) of the semicircle, we can use the formula for the circumference of a circle and take half of it:

extCircumference=2extπr ext{Circumference} = 2 ext{π}r

For the semicircle:

ext{Length} = rac{1}{2}(2 ext{π} imes 0.6)

Calculating this gives:

=0.5imes(2imesextπimes0.6)=1.88extm(correcttotwodecimalplaces)= 0.5 imes (2 imes ext{π} imes 0.6) \\ = 1.88 ext{ m (correct to two decimal places)}

Step 3

Find the perimeter of Ray's window.

96%

101 rated

Answer

To find the perimeter of the window, we need to add the length of the rectangle to the length of the semicircle and the diameter of the semicircle:

extPerimeter=extLengthoftherectangle+extLengthofthesemicircle+extDiameter ext{Perimeter} = ext{Length of the rectangle} + ext{Length of the semicircle} + ext{Diameter}

Substituting the values:

=1.5+1.88+1.2=4.58extm(correcttotwodecimalplaces)= 1.5 + 1.88 + 1.2 \\ = 4.58 ext{ m (correct to two decimal places)}

Thus, the perimeter of Ray's window is 4.58 metres.

Join the Junior Cycle students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;