Fractions and Decimals
From a rope 30 m long, a person cuts off as many pieces as possible, each 3 1/4 m long. What fraction of the whole will be left ?
Length of each piece = 3 1/4 = 13/4 m Maximum pieces that can be cut = 30/(13/4) = 9 ∴ Rope left = 30 - 13/4 x 9 = 120 - 117/4 = 3/4 m∴ Required fraction = 3/4/30 = 1/4
Let the length of lamppost = L mThen,first part = L/3and second part = (3/8) x L/3 = L/8 and third part = 6 m 50 cm = 6.50 mFirst part + second part + Third part = length of lamppost ⇒ L/3 + L/8 + 6.5 = L ⇒ L - L/3 - L/8 =6.5 ⇒ (24L - 8L - 3L)/24 = 6.5 ⇒ 13L/24 = 6.5 ∴ L = (65.x 24)/13 = 12 m
Sum of the decimal places = 7 .Since the last digit to the extreme right will be zero ( 5 * 4 = 20), so there will be 6 significant digits to the right of the decimal point....
Let the population of village = N Then, adult's population = 5N/8and adult females = 1/2 x 5N/8 = 5N/16 ∴ illiterate females = 4/5 of adult female population ⇒ 400 = 4/5 x 5N/16 ⇒ N = (400 x 16)/4∴ N = 1600
EXAMIANS