Answer:
7/4 which could also be written as 1 and 3/4
Answer:
let the unit digit be x
and the tens digit be y
so x+y = 9 ---> y = 9-x
the number is 10y+x
the number reversed is 10x + y
3(10y+x) = 8(10x + y)
30y + 3x = 80x + 8y
22y = 77x
2y = 7x
2(9-x) = 7x
18 - 2x = 7x
18=9x
x=2
y=7
the number is 72
check:
number is 72
reverse is 27
is 3(72) = 8(27)
Unknowns on one side, known on other.
2/5x - 4/5x = 30-25
-2/5x=5
X= -25/2
X=12.5
There are a couple of ways to look at this.
1) Set up a ratio: 2 cups sugar to 5 cups flour = 5 cups sugar to x cups flour
2/5 = 5/x
cross multiply
2x = 25
x = 12 1/2 cups flour
2) Look at the factor by which the cups of sugar was increased and increase
the cups of flour by the same factor.
2x = 5
x = 2.5
The sugar was increased by a factor of 2.5 so increase flour by same factor.
5(2.5) = 12 1/2 cups flour
