(i) Irfan says that he has 7 marbles more than five times the marbles Parmit has.

Question

Set up an equation in the following cases:

(i) Irfan says that he has 7 marbles more than five times the marbles Parmit has. Irfan has 37 marbles. (Take m to be the number of Parmit’* marbles.)

(ii) Laxmi’ father is 49 years old. He is 4 years older than three times Laxmi’ age. (Take Laxmi’* age to bey years)

(iii) The teacher tells the class that the highest marks obtained by a student in her class is twice the lowest marks plus 7. The highest score is 87. (Take the lowest score to be l.)

(iv) In an isosceles triangle, *** vertex angle is twice either base angle. (Let the base angle be A in degrees. Remember that the sum of angles of a triangle is 180 degrees).

Answer 1

(i) Let the number of marbles Parmit had be ‘m’
∴ Number of marbles Irfan has = Five times of parmits marble 5m.
To this 7 marbles more means = 5m + 7
∴ 5m + 7 = 37.

(ii) Let the age of Lakshmi be ‘y’ years
Three times of age = 3y
More than 4 years = 3y + 4
∴ Lakshmi’* father age be = 3y + 4
∴ 3y + 4 = 49

(iii) Let the lowest score be ‘l’
Twice the lowest score be = 2l
Plus seven = 2l + 1
∴ The highest score = 2l + 7
∴ 2l + 7 = 87

(iv) Let the base angle be b°
Vertex angle = Twice the base angle
∴ Vertex angle = 2b
Sum of the angles of an isosceles triangle is =180°
∴ 2b + b + b = 180° = 4b = 180°