Brain Teasers
Part by Part
Can you split 34 into 2 parts such that 4/7 of one part is equal to 2/5 of the other?
Answer
Let X and Y be the two parts.Then solving the equations
X+Y=34 and
(4/7)X=(2/5)Y,
we get X=14 and Y=20.
Hide Answer Show Answer
What Next?
View a Similar Brain Teaser...
If you become a registered user you can vote on this brain teaser, keep track of which ones you have seen, and even make your own.
Solve a Puzzle
Comments
I figured that the answers might be whole numbers so I tried splitting off 7 (4/7x7=4). Nope. Then I tried splitting off 14 (4/7x14= Yes!
i hate algebra
A couple seconds to do: 4 x 5 = 20; 2 x 7 = 14; 14 + 20 = 34
The easy way to do it (and how I suspect most people will do it) is to convert the fractions to a common denominator. This gives the first being 20/35 of the second and the second being 14/35 of the first, so the ratio between the parts is 14::20.
Conveniently, 14 + 20 = 34, so no more work was necessary.
The easy way to do it (and how I suspect most people will do it) is to convert the fractions to a common denominator. This gives the first being 20/35 of the second and the second being 14/35 of the first, so the ratio between the parts is 14::20.
Conveniently, 14 + 20 = 34, so no more work was necessary.
To post a comment, please create an account and sign in.
Follow Braingle!