Class X : HOTS Question Answers: Math Unit - 3 (Pair of linear equations)

Pair of linear equations

1.  At a certain time in a deer park, the number of heads and the number of legs of deer and human visitors were counted and it was found there were 39 heads & 132 legs.  Find the number of deer and human visitors in the park.

2. Find the value of p and q for which the system of equations represent coincident lines

3. 2x +3y = 7, (p+q+1)x +(p+2q+2)y = 4(p+q)+1
4. Students are made to stand in rows. If one student is extra in a row there would be 2 rows less. If one student is less in a row there would be 3 rows more. Find the number of students in the class.

5.  The larger of two supplementary angles exceeds the smaller by 180, find them.

6. A train covered a certain distance at a uniform speed.  If the train would have been 6km/hr faster, it would have taken 4hours less than the scheduled time.  And if the train were slower by 6km/hr, it would have taken 6 hours more than the scheduled time.  Find the distance of the journey.          

7.  A chemist has one solution which is 50% acid and a second which is 25% acid.  How much of each should be mixed to make 10 liters of 40% acid solution.