3
b)
[tex]5x - 4.81 = x + 2.19 \\ 5x - \frac{481}{100} = x + \frac{219}{100} \\ 5x - x = \frac{219}{100} + \frac{481}{100} \\ 4x = 700 \\ x = \frac{700}{4} \\ x = 175[/tex]
c)
[tex]2.1 \times (x + 4.5) = 7.2 \times 2.1 \\ \frac{21}{10} \times (x + \frac{45}{10} ) = \frac{72}{10} \times \frac{21}{10} \\ x + \frac{45}{10} = \frac{72}{10} \\ x = \frac{72}{10} - \frac{45}{10} \\ x = \frac{27}{10} \\ x = 2.7[/tex]
