Mathematics
Write true (T) or false (F) : (i) The smaller of the two numbers whose sum is 26 and the difference is 6 is 10. (ii) The solutions of an equation in variable z are the values of z for which L.H.S. = R.H.S. (iii) Sum of two consecutive even natural numbers is 24. This statement can be represented by the equation x + (2x + 2) = 24. (iv) 3x + 4 12 is a linear equation in one variable. (v) x = 4 is a solution of the equation .
Related Questions
The ages of A and B are in the ratio 2 : 5. After 6 years, their ages will be in the ratio 1 : 2. The present age of B is
- 20 years
- 24 years
- 30 years
- 36 years
Fill in the blanks :
(i) An equation involving one variable with highest power ……………, is called a linear equation in that variable.
(ii) The solution of an equation is also called …………… of the given equation.
(iii) The process in which we drop a term from one side of an equation and put it on the other side with sign changed is called …………… .
(iv) A linear equation can have at the most …………… solution(s).
(v) If thrice a number increased by 8 gives 23, then the number is …………… .
(vi) If x - 7 = 4, then 3x - 15 is equal to …………… .
Sanjay runs a computer repair service company. For an HP laptop, he charges ₹ 320 for diagnosis and ₹ 90 per hour for repairs. For a Dell laptop, he charges ₹ 480 for diagnosis and ₹ 70 per hour for repairs.
(1) Sanjay repairs an HP laptop of Mr Lal. He charges ₹ 950 for the work. How long did the repair work take place?
- 6 hours
- 7 hours
- 8 hours
- 9 hours
(2) Sanjay repairs a Dell laptop of Mr Gupta. The total charges were ₹ 830. How long did the repair work take place?
- 5 hours
- 6 hours
- 7 hours
- 8 hours
(3) He repairs an HP laptop and a Dell laptop of Mr Subhash. He found that the repair work for both the laptops took equal time and also the service charges of the two laptops were the same. How long did the repair work take place for each laptop ?
- 6 hours
- 7 hours
- 8 hours
- 9 hours
(4) What were the total service charges that Mr. Subhash had to pay for both the laptops ?
- ₹ 1040
- ₹ 1260
- ₹ 2040
- ₹ 2520
The ABS school organised Science competition for seventh class students. In this exam, there were 40 questions, all MCQ types. Three marks were awarded for each correct answer and one mark was deducted for each question that was answered incorrectly or left unanswered.
(1) Aryan scored 76 marks. How many questions did he answer correctly ?
- 23
- 25
- 7
- 29
(2) Ramya scored 84 marks. If she attempted all the questions, how many of her answers were incorrect ?
- 9
- 10
- 11
- 12
(3) Hema's score was double the number of questions she attempted correctly. How many of her answers were correct ?
- 10
- 15
- 20
- 25
(4) Bilok's score was the highest in the class. His score was 12 marks less than the maximum marks. How many of his answers were correct ?
- 35
- 36
- 37
- 38