THE RATIO OF HORSES AND COWS AT THE FARM (CAMBRIDGE PAST PAPER)

A farmer has 45 horses and 20 cows.
 (i)  Write this as a ratio horses : cows.
       Give your answer in its simplest form.
 (ii) The farmer wants the ratio horses : cows to equal 5 : 3.
        He keeps his 45 horses but buys some more cows. Work out the number of cows he must buy. 

Mathematics Cambridge IGCSE Test (0580 m16 qp 32) 

 Answer:
 (i) The ratio is always expressed in the simplest form
       45 : 20
       Divided by 5 to become
       9:4
 (ii) In this case, it must be answered by algebraic expression.
       Because we have not know how many cows more to be bought yet, so it is expressed by x.
       The algebraic expression is become
       45: (20+x)=5:3
       With cross multiplication
       45x3 = 5(20+x)
       135 = 100 + 5x
       35 = 5x
       7 = x
       So the number of cows he must buy are 7.


=====================================================

SIMILAR  QUESTION (EXAMPLE QUESTION ONLY)

One of Texas Attorney has 75 horses and 55 buffaloes.
(i) Write this as a ratio horses : buffaloes.
      Give your answer in its simplest form. 

(ii) The Texas Attorney wants the ratio horses : buffaloes to equal 5 : 4.
      He keeps his 75 horses but buys some more buffaloes.
      Work out the number of buffaloes Texas Attorney must buy.                                                                
Answer:

(i)The ratio is always expressed in the simplest form
    75 : 55
    Divided by 5 to become
    15:11

(ii)  In this question, have to processed algebraically.
                  Because Texas Attorney haven’t know how many buffaloes more to be bought yet, so it is  
                  expressed by x.
                  The algebraic expression is become
                  75: (55+x)=5:4
                  With cross multiplication
                  75x4 = 5(55+x)
                  300 = 275 + 5x
                  25 = 5x
                 5 = x
So the number of buffaloes TexasAttorney must buy are 5 buffaloes.

iklan atas artikel

Iklan Tengah Artikel 1

Iklan Tengah Artikel 2

Iklan Bawah Artikel