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Ratio and Proportion | Exercise

Question 21

27cm2 : 57cm2 = 18cm : 38cm

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  • Solution

  • Transcript

True

Consider the two ratios 27cm2 : 57cm2 = 18cm : 38cm

27/57 = 18/38

27/57 is further simplified by dividing both numerator and denominator by 3 we get,

= 9/19

18/38 is further simplified by dividing both numerator and denominator by 2 we get,

= 9/19

Hence, 9/19 = 9/19

Therefore, 27cm2 : 57cm2 = 18cm : 38cm

"hello students welcome to lido qna video session i am saf your math tutor and question for today is a small indoor greenhouse herbarium is made entirely of glass panes including its base which is held together with the tape it is 30 centimeter long 25 centimeter wide and 25 centimeter high so it is asked that first what is the area of the glass second how much of the tape is needed for trial edges to find this let us first of all see what is given length of the greenhouse is given let us say it is l and length is given as 30 centimeter then you have been given breath let us say it is b so breath is given that is 25 centimeter and you have also been given the height let us say it as h which is 25 centimeter now we should first of all find in the first question that is total surface area the total surface area of this greenhouse can be given by let us say it is a so a is equal to 2 into length into breath plus breath into height plus height into length so this will give us 2 into 30 into 25 plus breath into height that is 25 into 25 plus 30 into 25 again so that is as per the formula proceeding with further calculation that is 2 into 750 plus 25 into 25 that is 625 plus 750 and this is equal to 2 into 2125 so it comes out to be 4250 centimeter square so total surface area of the glass is four to five zero centimeter square now once we have found this we can proceed further with our second part of the question in the second part it is to ask that how much tape is needed for all 12 edges so let us continue our second part over here now see the figure which is drawn over here from the figure tape is required along the sides a b b c c d b a e f f g g h h e a h b e d g and cf these are the all sides for which the tape is required so total length of the tape will be four times length plus breadth plus height so this will become 4 into 30 plus 25 plus 25 and is equal to 320 centimeter so length of the tape will be 320 centimeter for all 12 edges so this is our final answer if you have any query you can drop it in our comment section and subscribe to lido for more such q a thank you for watching "

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Question 21

27cm2 : 57cm2 = 18cm : 38cm

  • Solution

  • Transcript

True

Consider the two ratios 27cm2 : 57cm2 = 18cm : 38cm

27/57 = 18/38

27/57 is further simplified by dividing both numerator and denominator by 3 we get,

= 9/19

18/38 is further simplified by dividing both numerator and denominator by 2 we get,

= 9/19

Hence, 9/19 = 9/19

Therefore, 27cm2 : 57cm2 = 18cm : 38cm

"hello students welcome to lido qna video session i am saf your math tutor and question for today is a small indoor greenhouse herbarium is made entirely of glass panes including its base which is held together with the tape it is 30 centimeter long 25 centimeter wide and 25 centimeter high so it is asked that first what is the area of the glass second how much of the tape is needed for trial edges to find this let us first of all see what is given length of the greenhouse is given let us say it is l and length is given as 30 centimeter then you have been given breath let us say it is b so breath is given that is 25 centimeter and you have also been given the height let us say it as h which is 25 centimeter now we should first of all find in the first question that is total surface area the total surface area of this greenhouse can be given by let us say it is a so a is equal to 2 into length into breath plus breath into height plus height into length so this will give us 2 into 30 into 25 plus breath into height that is 25 into 25 plus 30 into 25 again so that is as per the formula proceeding with further calculation that is 2 into 750 plus 25 into 25 that is 625 plus 750 and this is equal to 2 into 2125 so it comes out to be 4250 centimeter square so total surface area of the glass is four to five zero centimeter square now once we have found this we can proceed further with our second part of the question in the second part it is to ask that how much tape is needed for all 12 edges so let us continue our second part over here now see the figure which is drawn over here from the figure tape is required along the sides a b b c c d b a e f f g g h h e a h b e d g and cf these are the all sides for which the tape is required so total length of the tape will be four times length plus breadth plus height so this will become 4 into 30 plus 25 plus 25 and is equal to 320 centimeter so length of the tape will be 320 centimeter for all 12 edges so this is our final answer if you have any query you can drop it in our comment section and subscribe to lido for more such q a thank you for watching "

Our top 5% students will be awarded a special scholarship to Lido.

subject-cta
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