8th RATIONAL NUMBER

MATH COMPLETE STUDY

Q1. Express −35 as a rational number with denominator: (i) 20 (ii) −40

Q2. Arrange the following numbers in ascending order: 4 /− 9 , − 5 /12 ; 7/ − 18 ; − 2/ 3

Q3. Arrange the following numbers in descending order: − 5, 6/ ; − 7/ 12 ; − 13/ 28 ; 23/ − 24

Q4. Represent −25/6 on the number line.

Q5. Represent 42/3on the number line.

Q6. What number should be added to −78to get 49?

Q7. The sum of two rational numbers is −12. If one of the numbers is 56, find the other.

Q8. What number should be subtracted from −23 to get −12?

Q9. Subtract: −3213 from −65

Q10. Find the following products: (i) 16−21×145 (ii) 724×−48

Q11. Verify whether the given statement is true or not: (i) <59÷13) ÷ 52= 59÷(13÷52)

Q12. Divide the sum of 135and−127by the product of −317and1−2.

Q13. The product of two rational numbers is −169. If one of the numbers is −43, find the other.

Q14. Find three rational numbers between 4and5.

Q15. Find three rational numbers between 23and34.

Q16. A drum full of rice weights 4016kg. If the empty drum weights 1334kg, find the weight of rice in the drum.

Q17. A car is moving at an average speed of 4025km/h. How much distance will it cover in 712h?

Q18. Raju earns Rs16000/m. He spends 14of his income on food; 310of the remainder on house rent and 521of the remainder on education of children. How much money is still left with him?

Q19. After reading 79of a book, 40pages are left. How many pages are there in the book?

Q20. Are these pairs forming pair of equivalent rational numbers? (i) 1435and2145 (ii) −1226and1839

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