1
$\begingroup$

I'm trying to help my little sister out but I can't seem to figure it out.

Here is the question:

John fish weight 8 times as much as her parakeet. Together the pet's weight 63 ounces. How much does the fish weight?

The only answer I can think of is 7.875.

$\endgroup$
  • $\begingroup$ They may be expected to do it by a "guess and check" process. Guess that the parakeet weighs one ounce. Then the fish weighs $8$ ounces, for a total of $9$. That's definitely not $63$! However, $63=9\times 7$, so if we make the parakeet weigh $7$ times as much as our initial guess, everything will be OK. So parakeet $7$, fish therefore $56$. $\endgroup$ – André Nicolas Sep 28 '14 at 16:38
1
$\begingroup$

Let the weight of the parakeet be $x$. Then John's fish is eight times that weight: $8x.$

Then the weight of both of them together is $x+8x=63$.

Simplifying the left side, we get $9x=63\implies x=7$

We can even check that this is right. Since we said that $x=7$, this means the weight of the parakeet is 7 ounces. The fish weighs eight times more, so $8\times 7=56$. Then together, they weigh $7+56=63$ ounces.

So, the fish weighs $8x=8\times 7=56$ ounces.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.