Answer:
x = 1
Step-by-step explanation:
1/2x - 3/4 = 3/8 - 5/8x
The LCD is 8. Lets change every fraction to a denominator of 8.
4/8x - 6/8 = 3/8 - 5/8x
Now multiply both sides by 8.
4x - 6 = 3 - 5x
Add 5x to both sides. Add 6 to both sides.
9x = 9
Divide both sides by 9.
x = 1
Because there are 4 students who passed in all subjects, we can say that only 2 students passed in English and Mathematics only, only 3 students passed in Mathematics and Science only, and no one passed in English and Science only.
Given that we have deduced the number of students who passed in two subjects, we can now solve for the number of students who passed only one subject.
English = 15 - (4 + 2 + 0) = 9
Mathematics = 12 - (4 + 3 + 2) = 3
Science = 8 - (4 + 3 + 0) = 1
1. In English but not in Science,
9 + 2 = 11
2. In Mathematics and Science but not in English
3 + 3 + 1 = 7
3. In Mathematics only
= 3
3. More than one subject only
3 + 4 + 2 + 9 = 18
It will really be helpful if you draw yourself a Venn Diagram for this item.
Assuming the possible digits are from 0-9, there are 10*9*8 possibilities which come out to 720
First, create an equation with the criteria given.
If we let x be your number,

(

is twice the product of 3 and x, and if it exceeds

by 10, then we add 10 to

to make the two sides of the equation equal.)
Now, solve for

.