1. Manish's mother is one more than 5 times his present age.
4 years ago the product of their ages is 220. Find their present
Answers
Given
Manish's Mother is one more than 5 times his present age.
4 years ago their product of their ages was 220.
To Find
We have to find their present ages
Let the present age of Manish be 'x'
Then ,his mother's present age be = 1+5x
4 years ago ,
➞Age of Manish 4 years ago = x-4
➞Age of Manish's mother 4 years ago = (1+5x)-4
According to the question:
Their product of their ages is 220 then,
➞(x-4)(1+5x)-4=220
➞(x-4)(5x+1)=220+4
➞x(5x+1)-4(5x+1)=224
➞5x²+x-20x-4=224
➞5x²-19x=228
➞5x²-19x-228=0
Factorise it by using quadratic formula
a=5,b= -19 & c= -228
x=-b±√b²-4ac ÷2a
➞x=-(-19)±√(-19)²-4(5)(-228) /2(5)
➞x=19±√361-(-4560) /10
➞x= 19±√4921/10
➞x=19±√4921/10
➞x=19/10±√4921/10
➞x= 8.91 or x= -5.11
Hence,age can't be negative so,we will take positive value of x
Hence,x = 8.91 so,we take 9 ( rounded off value)
Therefore, Present age of Manish is 9 years
Age of Manish's mother = 1+5x= 46 years
Answer:
Let the present age of Manish be 'x'
Then ,his mother's present age be = 1+5x
4 years ago ,
➞Age of Manish 4 years ago = x-4
➞Age of Manish's mother 4 years ago = (1+5x)-4
According to the question:
Their product of their ages is 220 then,
➞(x-4)(1+5x)-4=220
➞(x-4)(5x+1)=220+4
➞x(5x+1)-4(5x+1)=224
➞5x²+x-20x-4=224
➞5x²-19x=228
➞5x²-19x-228=0
Factorise it by using quadratic formula
a=5,b= -19 & c= -228
x=-b±√b²-4ac ÷2a
➞x=-(-19)±√(-19)²-4(5)(-228) /2(5)
➞x=19±√361-(-4560) /10
➞x= 19±√4921/10
➞x=19±√4921/10
➞x=19/10±√4921/10
➞x= 8.91 or x= -5.11
Hence,age can't be negative so,we will take positive value of x
Hence,x = 8.91 so,we take 9 ( rounded off value)
Therefore, Present age of Manish is 9 years
Age of Manish's mother = 1+5x= 46 years
Step-by-step explanation:
Hope it helps dear mark as brainliest please...