CBSE Class 7 Mathematics Rational Numbers Assignment Set 07

Question. Divide \( \frac{25}{32} \) by \( \frac{8}{5} \)
Answer: \( \frac{125}{256} \)

Question. Divide \( -\frac{8}{15} \) by \( -\frac{4}{25} \)
Answer: \( \frac{10}{3} \)

Question. Simplify \( 2\frac{1}{5} \div 3\frac{1}{4} \)
Answer: \( \frac{44}{65} \)

Question. Prove that \( \frac{5}{11} \div \frac{15}{22} \neq \frac{15}{22} \div \frac{5}{11} \)
Answer: LHS = \( \frac{2}{3} \), RHS = \( \frac{3}{2} \). Since LHS \( \neq \) RHS, the statement is proved.

Question. Compute \( \left(\frac{2}{3} \div \frac{4}{15}\right) \div \frac{1}{3} \) and \( \frac{2}{3} \div \left(\frac{4}{15} \div \frac{1}{3}\right) \). Are they equal?
Answer: Not equal

Question. The product of two numbers is \( -\frac{35}{81} \). If one of them is \( -\frac{7}{18} \), find the other.
Answer: \( \frac{10}{9} \)

Question. Calculate \( \left(\frac{2}{3} \div \frac{5}{6}\right) \times \left(-\frac{1}{8}\right) \)
Answer: \( -\frac{1}{10} \)

Question. Divide the sum of \( 2\frac{1}{3} \) and \( 1\frac{1}{7} \) by the difference of \( 3\frac{1}{3} \) and \( 1\frac{1}{2} \)
Answer: \( \frac{146}{77} \)

Question. The length of a rope is \( 9\text{ m} \). How many pieces of \( 2\frac{1}{4}\text{ m} \) can be cut from this rope?
Answer: 4

Question. By what number should we multiply \( \frac{14}{39} \) to get the product as \( -\frac{7}{13} \)?
Answer: \( -\frac{2}{3} \)

Question. The cost of \( 2\frac{3}{4}\text{ metres} \) of cloth is \( \text{Rs } 73\frac{1}{3} \). Find the cost of cloth per metre.
Answer: \( \text{Rs } 26\frac{2}{3} \)

Question. Divide the sum of \( \frac{13}{5} \) and \( \frac{-12}{7} \) by the product of \( \frac{-31}{7} \) and \( \frac{1}{-2} \)
Answer: \( \frac{2}{5} \)

Question. By what number should \( -\frac{33}{8} \) be divided to get \( -\frac{11}{2} \)?
Answer: \( \frac{3}{4} \)

Question. By what rational number should \( -\frac{8}{39} \) be multiplied to obtain \( 26 \)?
Answer: \( -\frac{507}{4} \)

Question. The price of \( 12\text{ books} \) is \( \text{Rs } 181\frac{1}{5} \). Find the price of each book.
Answer: \( \text{Rs } 15.10 \)