[tex]a) \frac{1}{100} \times 100 = \frac{100}{100} = 1[/tex]
[tex]b) \frac{5}{100} \times 20 = \frac{5 \times 20}{100} = \frac{100}{100} = 1[/tex]
[tex]c) \frac{10}{100} \times 40 = \frac{10 \times 40}{100} = \frac{400}{100} = 4[/tex]
[tex]d) \frac{12}{100} \times 375 = \frac{12 \times 375}{100} = \frac{4500}{100} = 45[/tex]