The value (i) 0.56, (ii) 0.81 and (iii) 200
To solve this problem, we have to use a concept known as difference of two squares.
a)
Given two decimals and we are to find the difference between their squares,
[tex]0.9^2 - 0.5^2\\(\frac{9}{10})^2 - (\frac{1}{2})^2 = \\ \frac{81}{100} - \frac{1}{4} = \frac{81 - 25}{100} = \frac{56}{100} = \frac{14}{25} = 0.56[/tex]
b)
We have two decimals
[tex]1.5^2 - 1.2^2 = 2.25 - 1.44 = 0.81[/tex]
c)
We would find the difference of two squares here
[tex]100.5^2 - 99.5^2 = 200[/tex]
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