Tea Pei Si's answer to Claressa Clara's Secondary 4 E Maths Malaysia question.

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Tea Pei Si
Tea Pei Si's answer
25 answers (Tutor Details)
1st
Step one: find the volume of the whole solid (including the cylinder). This is done by first finding the area of trapezium ABFE, then multiplied by 30.

Step two: find volume of cylinder by minusing volume of whole solid with the volume of remaining solid where cylinder part is removed. Given in question what the value of the latter.

Step three: make an equation using the formula for calculating volume of cylinder. Then sub in the values related to this cylinder (you have found in above workings and what was given in qn). In this case, height of cylinder and volume of cylinder.

Step four: solve the equation to find r.