方程...

If we divide 80 into two parts sush that one part is2/3of the other,then the larger part is....

Let the larger part be a,
Smaller part = 2/3a
a + 2/3a = 80
1 2/3 a = 80
5a/3 = 80
a = 80 * 3 /5
a = 48


If I think of a number x and decrease it by 5 then the result is 15 more than half of x. which number did I think....

Let the number I think be x,
x - 5 = 15 + 1/2 x
x - ½ x = 15 + 5
½ x = 20
x = 40

Ans. The number I think is 40.

If I think of a number x and decrease it by 5 then the result is 15 more than half of x. which number did I think....