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    Question:
    A chord of a circle, radius 20cm, divides the circumference in the ratio 1:3. Find the ratio of the areas of the segments into which the circle is divided by the chord.

    I thought i had radian measures covered inside-out until I came across this question lol. please help!
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    (Original post by SM45367)
    Question:
    A chord of a circle, radius 20cm, divides the circumference in the ratio 1:3. Find the ratio of the areas of the segments into which the circle is divided by the chord.

    I thought i had radian measures covered inside-out until I came across this question lol. please help!
    Sketch it. Remember what ratios are, so what can you saw the arc length of the circle bounded by the chord is? Link the end bits to the radius and consider a sector/triangle to find the required area and then divide it by the area of the whole circle.

    Remember that the arclength will determine the angle between the two red lines (both radii):

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    (Original post by Zacken)
    Sketch it. Remember what ratios are, so what can you saw the arc length of the circle bounded by the chord is? Link the end bits to the radius and consider a sector/triangle to find the required area and then divide it by the area of the whole circle.

    Remember that the arclength will determine the angle between the two red lines (both radii):

    I did sketch it. worked out the arc length of the minor segment (using the ratio) and then found theta of this arc. From here i found area of minor segment. area of circle- area of minor= major segment. put it into ratio form and got 1:11, however answer is 1:10, and tbh i really can't find what im doing wrong.
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    (Original post by SM45367)
    I did sketch it. worked out the arc length of the minor segment (using the ratio) and then found theta of this arc. From here i found area of minor segment. area of circle- area of minor= major segment. put it into ratio form and got 1:11, however answer is 1:10, and tbh i really can't find what im doing wrong.
    You should have included all this from the outset. Post up your workings with the numbers used and whatevs.
 
 
 
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