Let Ravi’s present age be x years. After fifteen years, Ravi’s age = 4x years. Fifteen years from now, Ravi’s age = (x+15) years. According to question, 4x=x+15 ⇒ 4x-x=15 [Transposing x to L.H.S.] ⇒ 3x=15 ⇒ 3x/3=15/3 [Dividing both sides by 3] ⇒ x=5 years Hence, Ravi’s present age be 5 years. for moRead more
Let Ravi’s present age be x years. After fifteen years, Ravi’s age = 4x years.
Fifteen years from now, Ravi’s age = (x+15) years.
According to question, 4x=x+15
⇒ 4x-x=15 [Transposing x to L.H.S.]
⇒ 3x=15
⇒ 3x/3=15/3 [Dividing both sides by 3]
⇒ x=5 years
Let Baichung’s age be x years, then Baichung’s father’s age = (x+29) years and Baichung’s granddaughter’s age = (x+29+26) = (x+55) years. According to condition, x+x+29+x+55=135 ⇒ 3x+84=135 ⇒ 3x+84-84=135-84 [Subtracting 84 from both sides] ⇒ 3x=51 ⇒ 3x/3=51/3 [Dividing both sides by 3] ⇒ x=17 yearsRead more
Let Baichung’s age be x years, then Baichung’s father’s age = (x+29) years and
Baichung’s granddaughter’s age = (x+29+26) = (x+55) years.
According to condition, x+x+29+x+55=135
⇒ 3x+84=135
⇒ 3x+84-84=135-84 [Subtracting 84 from both sides]
⇒ 3x=51
⇒ 3x/3=51/3 [Dividing both sides by 3]
⇒ x=17 years
Hence, Baichung’s age = 17 years, Baichung’s father’s age = 17 + 29 = 46 years and
Baichung’s granddaughter’s age = 17 + 29 + 26 = 72 years.
Let the number of girls be x. Then, the number of boys = x+8. According to the question, x+8/x=7/5 ⇒ 5(x+8)=7x ⇒ 5x+40=7x ⇒ 5x-7x = -40 [Transposing 7x to L.H.S. and 40 to R.H.S.] ⇒ -2x=-40 ⇒ -2x/-2=-40/-2 [Dividing both sides by 2] ⇒ x=20 Hence the number of girls = 20 and number of boys = 20 + 8Read more
Let the number of girls be x. Then, the number of boys = x+8.
According to the question, x+8/x=7/5
⇒ 5(x+8)=7x ⇒ 5x+40=7x
⇒ 5x-7x = -40 [Transposing 7x to L.H.S. and 40 to R.H.S.]
⇒ -2x=-40
⇒ -2x/-2=-40/-2 [Dividing both sides by 2]
⇒ x=20
Hence the number of girls = 20 and number of boys = 20 + 8 = 28.
Let the present ages of Rahul and Haroon be 5x years and 7x years respectively. According to condition, (5x+4)+(7x+4)=56 ⇒ 12x+8=56 ⇒ 12x+8-8=56-8 [Subtracting 8 from both sides] ⇒ 12x/8 ⇒ 12x/12=48/12 [Dividing both sides by 12] ⇒ x=4 Hence, present age of Rahul = 5 x 4 = 20 years and present age oRead more
Let the present ages of Rahul and Haroon be 5x years and 7x years respectively.
According to condition, (5x+4)+(7x+4)=56
⇒ 12x+8=56
⇒ 12x+8-8=56-8 [Subtracting 8 from both sides]
⇒ 12x/8
⇒ 12x/12=48/12 [Dividing both sides by 12]
⇒ x=4
Hence, present age of Rahul = 5 x 4 = 20 years and present age of Haroon = 7 x 4 = 28 years.
Let the three consecutive integers be x,x+1 and x+2 According to the question, 2x+3(x+1)+4(x+2)=74 ⇒ 2x+3x+3+4x+8=74 ⇒ 9x+11=74 ⇒ 9x+11-11=74-11 [Subtracting 11 from both sides] ⇒ 9x+63 ⇒ 9x/9=63/9 [Dividing both sides by 9] ⇒ x=7 Hence first integer = 7, second integer = 7 + 1 = 8 and third integerRead more
Let the three consecutive integers be x,x+1 and x+2
According to the question, 2x+3(x+1)+4(x+2)=74
⇒ 2x+3x+3+4x+8=74
⇒ 9x+11=74
⇒ 9x+11-11=74-11 [Subtracting 11 from both sides]
⇒ 9x+63
⇒ 9x/9=63/9 [Dividing both sides by 9]
⇒ x=7
Hence first integer = 7, second integer = 7 + 1 = 8 and third integer = 7 + 2 = 9.
Fifteen years from now Ravi’s age will be four times his present age. What is Ravi’s present age?
Let Ravi’s present age be x years. After fifteen years, Ravi’s age = 4x years. Fifteen years from now, Ravi’s age = (x+15) years. According to question, 4x=x+15 ⇒ 4x-x=15 [Transposing x to L.H.S.] ⇒ 3x=15 ⇒ 3x/3=15/3 [Dividing both sides by 3] ⇒ x=5 years Hence, Ravi’s present age be 5 years. for moRead more
Let Ravi’s present age be x years. After fifteen years, Ravi’s age = 4x years.
Fifteen years from now, Ravi’s age = (x+15) years.
According to question, 4x=x+15
⇒ 4x-x=15 [Transposing x to L.H.S.]
⇒ 3x=15
⇒ 3x/3=15/3 [Dividing both sides by 3]
⇒ x=5 years
Hence, Ravi’s present age be 5 years.
for more answers vist to:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/
Baichung’s father is 26 years younger than Baichung’s grandfather and 29 years older than Baichung. The sum of the ages of all the three is 135 years. What is the age of each one of them?
Let Baichung’s age be x years, then Baichung’s father’s age = (x+29) years and Baichung’s granddaughter’s age = (x+29+26) = (x+55) years. According to condition, x+x+29+x+55=135 ⇒ 3x+84=135 ⇒ 3x+84-84=135-84 [Subtracting 84 from both sides] ⇒ 3x=51 ⇒ 3x/3=51/3 [Dividing both sides by 3] ⇒ x=17 yearsRead more
Let Baichung’s age be x years, then Baichung’s father’s age = (x+29) years and
Baichung’s granddaughter’s age = (x+29+26) = (x+55) years.
According to condition, x+x+29+x+55=135
⇒ 3x+84=135
⇒ 3x+84-84=135-84 [Subtracting 84 from both sides]
⇒ 3x=51
⇒ 3x/3=51/3 [Dividing both sides by 3]
⇒ x=17 years
Hence, Baichung’s age = 17 years, Baichung’s father’s age = 17 + 29 = 46 years and
Baichung’s granddaughter’s age = 17 + 29 + 26 = 72 years.
for more answers vist to:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/
The number of boys and girls in a class are in the ratio 7: 5. The number of boys is 8 more than the number of girls. What is the total class strength?
Let the number of girls be x. Then, the number of boys = x+8. According to the question, x+8/x=7/5 ⇒ 5(x+8)=7x ⇒ 5x+40=7x ⇒ 5x-7x = -40 [Transposing 7x to L.H.S. and 40 to R.H.S.] ⇒ -2x=-40 ⇒ -2x/-2=-40/-2 [Dividing both sides by 2] ⇒ x=20 Hence the number of girls = 20 and number of boys = 20 + 8Read more
Let the number of girls be x. Then, the number of boys = x+8.
According to the question, x+8/x=7/5
⇒ 5(x+8)=7x ⇒ 5x+40=7x
⇒ 5x-7x = -40 [Transposing 7x to L.H.S. and 40 to R.H.S.]
⇒ -2x=-40
⇒ -2x/-2=-40/-2 [Dividing both sides by 2]
⇒ x=20
Hence the number of girls = 20 and number of boys = 20 + 8 = 28.
for more answers vist to:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/
The ages of Rahul and Haroon are in the ratio 5:7. Four years later the sum of their ages will be 56 years. What are their present ages?
Let the present ages of Rahul and Haroon be 5x years and 7x years respectively. According to condition, (5x+4)+(7x+4)=56 ⇒ 12x+8=56 ⇒ 12x+8-8=56-8 [Subtracting 8 from both sides] ⇒ 12x/8 ⇒ 12x/12=48/12 [Dividing both sides by 12] ⇒ x=4 Hence, present age of Rahul = 5 x 4 = 20 years and present age oRead more
Let the present ages of Rahul and Haroon be 5x years and 7x years respectively.
According to condition, (5x+4)+(7x+4)=56
⇒ 12x+8=56
⇒ 12x+8-8=56-8 [Subtracting 8 from both sides]
⇒ 12x/8
⇒ 12x/12=48/12 [Dividing both sides by 12]
⇒ x=4
Hence, present age of Rahul = 5 x 4 = 20 years and present age of Haroon = 7 x 4 = 28 years.
for more answers vist to:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/
Three consecutive integers are such that when they are taken in increasing order and multiplied by 2, 3 and 4 respectively, they add up to 74. Find these numbers.
Let the three consecutive integers be x,x+1 and x+2 According to the question, 2x+3(x+1)+4(x+2)=74 ⇒ 2x+3x+3+4x+8=74 ⇒ 9x+11=74 ⇒ 9x+11-11=74-11 [Subtracting 11 from both sides] ⇒ 9x+63 ⇒ 9x/9=63/9 [Dividing both sides by 9] ⇒ x=7 Hence first integer = 7, second integer = 7 + 1 = 8 and third integerRead more
Let the three consecutive integers be x,x+1 and x+2
According to the question, 2x+3(x+1)+4(x+2)=74
⇒ 2x+3x+3+4x+8=74
⇒ 9x+11=74
⇒ 9x+11-11=74-11 [Subtracting 11 from both sides]
⇒ 9x+63
⇒ 9x/9=63/9 [Dividing both sides by 9]
⇒ x=7
Hence first integer = 7, second integer = 7 + 1 = 8 and third integer = 7 + 2 = 9.
for more answers vist to:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/