PPT: Ratio and Proportion | Mathematics for Class 5 PDF Download

 Page 1


Ratios and
Proportions
U s i n g r a t i o s t o c o m p ar e q u a n t i t i e s
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Ratios and
Proportions
U s i n g r a t i o s t o c o m p ar e q u a n t i t i e s 2 a p p l e s f o r e v e r y 5 b a n a n a s R a t i o s a r e u s e d t o c o m p a r e t h e n u m b e r o f o n e t h i n g t o a n o t h e r . I t ' s w r i t t e n i n t h e f o r m a : b , w h i c h i s r e a d a s " a t o b . " Understanding Ratios
E x a m p l e :
T h e r a t i o o f t h e n u m b e r o f a p p l e s t o t h e n u m b e r o f b a n a n a s i s 2 : 5
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Ratios and
Proportions
U s i n g r a t i o s t o c o m p ar e q u a n t i t i e s 2 a p p l e s f o r e v e r y 5 b a n a n a s R a t i o s a r e u s e d t o c o m p a r e t h e n u m b e r o f o n e t h i n g t o a n o t h e r . I t ' s w r i t t e n i n t h e f o r m a : b , w h i c h i s r e a d a s " a t o b . " Understanding Ratios
E x a m p l e :
T h e r a t i o o f t h e n u m b e r o f a p p l e s t o t h e n u m b e r o f b a n a n a s i s 2 : 5
2 : 5 2 : 7
P a r t t o w h o l e r a t i o ( A p p l e ) P a r t t o p a r t r a t i o Example
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Ratios and
Proportions
U s i n g r a t i o s t o c o m p ar e q u a n t i t i e s 2 a p p l e s f o r e v e r y 5 b a n a n a s R a t i o s a r e u s e d t o c o m p a r e t h e n u m b e r o f o n e t h i n g t o a n o t h e r . I t ' s w r i t t e n i n t h e f o r m a : b , w h i c h i s r e a d a s " a t o b . " Understanding Ratios
E x a m p l e :
T h e r a t i o o f t h e n u m b e r o f a p p l e s t o t h e n u m b e r o f b a n a n a s i s 2 : 5
2 : 5 2 : 7
P a r t t o w h o l e r a t i o ( A p p l e ) P a r t t o p a r t r a t i o Example
A n e q u a t i o n t h a t s t a t e s t h a t t w o r a t i o s a r e e q u a l i s c a l l e d p r o p o r t i o n . PROPORTION
Example : Are 2 : 5 equivalent to 12 : 30 ?
We know, 2/5 = 12 / 30
Hence, 2 : 5 = 12 : 30.
? The first and fourth terms of the proportion are called
Extremes.
? The second and the third terms are called Means.
? Two ratios are in proportion if the
Product of extremes = Product of means.
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Ratios and
Proportions
U s i n g r a t i o s t o c o m p ar e q u a n t i t i e s 2 a p p l e s f o r e v e r y 5 b a n a n a s R a t i o s a r e u s e d t o c o m p a r e t h e n u m b e r o f o n e t h i n g t o a n o t h e r . I t ' s w r i t t e n i n t h e f o r m a : b , w h i c h i s r e a d a s " a t o b . " Understanding Ratios
E x a m p l e :
T h e r a t i o o f t h e n u m b e r o f a p p l e s t o t h e n u m b e r o f b a n a n a s i s 2 : 5
2 : 5 2 : 7
P a r t t o w h o l e r a t i o ( A p p l e ) P a r t t o p a r t r a t i o Example
A n e q u a t i o n t h a t s t a t e s t h a t t w o r a t i o s a r e e q u a l i s c a l l e d p r o p o r t i o n . PROPORTION
Example : Are 2 : 5 equivalent to 12 : 30 ?
We know, 2/5 = 12 / 30
Hence, 2 : 5 = 12 : 30.
? The first and fourth terms of the proportion are called
Extremes.
? The second and the third terms are called Means.
? Two ratios are in proportion if the
Product of extremes = Product of means.
Example : Are 20, 40, 60 and 80 in proportion.
 Solution : We have 20 : 40  =  20/40  =  2/4  =  1/2
Also, 
             60/80  =  6/8  =  3/4
Thus 20 : 40 are not in proportion to 60 : 80