BECE Mathematics 2017 Paper

Change the decimals to the form whole number $\times 10^{a}$Where the power (a) is the number of times you have to move the decimal point in order to get a whole number When you move to the right, the power is negative and when you move to the left, the power is positive $0.00492 = 492 \times 10^{-5}$ (The decimal point has to be moved five (5) times to the right)$0.041 = 41 \times 10^{-3}$ (The decimal point has to be moved three (3) times to the right)From the law of indices $\frac{a^m}{a^n} = a^{m-n}$$\frac{0.00492}{0.041} = \frac{492 \times 10^{-5}}{41 \times 10^{-3}}$41 goes into 492, 12 times$\frac{10^{-5}}{10^{-3}} = 10^{-5-(-3)}$ from the law of indices$\frac{492 \times 10^{-5}}{41 \times 10^{-3}} = 12 \times 10^{-5-(-3)}$-- or -(-) = +$12 \times 10^{-5-(-3)} = 12 \times 10^{-5+3} = 12 \times 10^{-2}$Now change the form back to decimals by moving to the left the number of times of the power (2)NOTE: we moved to the left because the power is negative (-2)$12 = 12.0$If you move the decimal two (2) times to the left, you will end up to $0.12$