a two digit number is 4 times the sum of digits it is also equal to 3 times the product of digits find the number
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Answered by
4
Let's call the two digit number "ab"
According to the problem, "ab" = 4(a+b) = 3(a*b)
"a" and "b" are integers, so "ab" = (10a + b), the same way that "23" = (10*2 + 3).
_____
(10a +b) = 4(a + b) = 3(a * b)
10a + b = 4a + 4b = 3ab
Let's solve one half of this equation for a, in terms of b:
10a + b = 4a + 4b ... combine like terms
6a = 3b ... divide both sides by 3
2a = b
_____
Now we can substitute the equality (2a = b) in for b:
10a + b = 3ab ... solve one side at a time:
5b + b = 3ab
6b = 3ab ... now divide by 3
2b = ab ... so a*b = 2*b, therefore a = 2
Now subsitute the value a = 2 into the equality (2a = b)
2a = b
2*2 = b
b = 4
_____
So the original number is (10a + b) = (10*2 + 4) = (20 + 4) = 24
According to the problem, "ab" = 4(a+b) = 3(a*b)
"a" and "b" are integers, so "ab" = (10a + b), the same way that "23" = (10*2 + 3).
_____
(10a +b) = 4(a + b) = 3(a * b)
10a + b = 4a + 4b = 3ab
Let's solve one half of this equation for a, in terms of b:
10a + b = 4a + 4b ... combine like terms
6a = 3b ... divide both sides by 3
2a = b
_____
Now we can substitute the equality (2a = b) in for b:
10a + b = 3ab ... solve one side at a time:
5b + b = 3ab
6b = 3ab ... now divide by 3
2b = ab ... so a*b = 2*b, therefore a = 2
Now subsitute the value a = 2 into the equality (2a = b)
2a = b
2*2 = b
b = 4
_____
So the original number is (10a + b) = (10*2 + 4) = (20 + 4) = 24
Answered by
30
Here is your solutions
Let the one's digit be x.
ten's digit be y.
Original number = 10x + y
given that the number is four times the sum of the number, i.e., 4(x + y).
=> 10x + y = 4(x + y)
=> 10x + y = 4x + 4y
=> 10x - 4x + y - 4y = 0
=> 6x - 3y = 0
=> 3(2x - y ) = 0
=> 2x - y = 0
=> 2x = y
given that it is also equal to 3 times the product of digits, i.e, 10x + y = 3xy.
y = 2x and 10x+y = 3xy
on putting value of y = 2x in
=> 10x + y = 3xy.
=> 10x + 2x = 3x( 2x )
=> 12x = 6x²
=> 12x - 6x² = 0
=> 6x ( 2 - x) = 0
So, x = 0 and x = 2
x = 2
On putting value of x in y = 2x.
we get;
y = 2x
=> y = 2 × 2
=> y = 4
So,
Original number = 10x + y
=> 10 × 2 + 4
=> 20 + 4
=> 24
hope you happy
Let the one's digit be x.
ten's digit be y.
Original number = 10x + y
given that the number is four times the sum of the number, i.e., 4(x + y).
=> 10x + y = 4(x + y)
=> 10x + y = 4x + 4y
=> 10x - 4x + y - 4y = 0
=> 6x - 3y = 0
=> 3(2x - y ) = 0
=> 2x - y = 0
=> 2x = y
given that it is also equal to 3 times the product of digits, i.e, 10x + y = 3xy.
y = 2x and 10x+y = 3xy
on putting value of y = 2x in
=> 10x + y = 3xy.
=> 10x + 2x = 3x( 2x )
=> 12x = 6x²
=> 12x - 6x² = 0
=> 6x ( 2 - x) = 0
So, x = 0 and x = 2
x = 2
On putting value of x in y = 2x.
we get;
y = 2x
=> y = 2 × 2
=> y = 4
So,
Original number = 10x + y
=> 10 × 2 + 4
=> 20 + 4
=> 24
hope you happy
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