Page 68 - Mathematics
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or dividing both terms of a ratio by the    a : b  = 3: 6
            same number does not change the ratio.      b : c  6:10=
            In other words, 2: 4  4:8 (multiplying                         3: 6 :10  and
            each term of the ratio by 2). The ratio    Therefore,  : :abc =
                                                         : =
            can be reduced to its lowest terms by       ac    3:10.
            expressing the ratio as a fraction and
            simplify it to its lowest term.            Example 4.3


               Example 4.1                             Jaha and Siwema shared 40,000
                                                       Tanzanian shillings. Jaha received
               Simplify 48:36.                         15,000 Tanzanian shillings and Siwema
    Tanzania Institute of Education
                                                       received 25,000 Tanzanian shillings.
               Solution                                Find the ratio of the amount of money
               Given  48:36                            each of them received.
               The Given ratio can be written in

               fraction as   48                        Solution
                          36                           The ratio is written as 15,000 to

               Dividing the numerator and              25,000 or
               denominator by 12 gives,                15,000 25,000÷  =  15,000
                   48  =  4                                              25,000

                       36  3                                                     =  3
               Therefore, 48:36 in its simplified                        5
               form is 4:3.                            Therefore, the ratio of the amount of
                                                       money received by Jaha and Siwema
               Example 4.2                             is 3:5.


               Given a:b = 1:2 and b:c = 3:5, find     Example 4.4
               a:b:c and a:c.

               Solution                                A man’s monthly income is
               Given  :ab = 1: 2  and  :bc =  3:5.     1,274,000 Tanzanian shillings.
                                                       He spends 1,078,000 Tanzanian
    Mathematics Form One  by 2 as follows:   3:5       ratio between his income to
               b is in both ratios, so make the two
                                                       shillings every month. Find the
               ratios equivalent by multiplying
                     1: 2  by 3 and  :bc =
               ab
                 :
                                                       expenditure and savings to income.
                                                       Solution
                 : ab =
                     (1: 2) 3×
                                                       Income to expenditure ratio:
                 : bc =
                     (3:5) 2×


                                                  62   Given, income = Tshs 1,274,000




                                                                                        25/10/2024   09:51:17
   Mathematics form 1.indd   62                                                         25/10/2024   09:51:17
   Mathematics form 1.indd   62
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