Check my math?

Factual Questions
1

I’m watching Tugboat Annie. A character has a homework problem:

If a fish weighs 10 pounds, and its body weighs twice as much as its head, and its head weighs wtice as much as its tail, how much would its tail weigh? Assigning T as the weight of the tail, I come up with this:

10 = T + 2T + 2 (2T)
10 = T + 2T +4T
10 = 7T
T ≈ 1.43 pounds

That is, The weight of the tail plus twice the weight of the tail (weight of the head) plus twice the weight of the head (four times the weight of the tail) equals 10 pounds.

Am I doing this right? (It’s been a while…)

2

I worked it out the same way. Looks right to me.

3

Looks right to me. The way the problem is phrased is that the entire weight of the fish is 7 times the weight of its tail alone, as you put it.

The fish consists of:

Head = 2 tails
Body = 4 tails
Tail itself = 1 tail

So the fish adds up to 7 tails.

4

Thanks.

5

That’s correct if you make the rather weird assumption that the fish’s head, tail and body are three disjoint parts of the fish. Using more normal terminology, where the head and tail are part of the body, the tail weighs 2.5 pounds, the head weighs 5 pounds, and the whole body weighs 10 pounds.

6

I didn’t write the script. :wink: I assume the question, which is unanswered in the film, was meant to sound complicated. Since the head, ‘body’ and tail are separated in the question, I took the values as given.

7

Yeah, it depends what part of the fish is part of the body.
If the head and tail are part of the body then the tail weighs 2.5 lbs.
If the head is distinct from the body then the tail weighs ~1.67 lbs.
If the head and tail are distinct from the body then the math in the op holds.

8

That’s how I read it, and 1.67 is the result I got.

9

No, I will not check your math.

10

Yes, 1/7 of 10 lbs is how I read it.

11

The question is totally ambiguous.

12

As opposed to partially ambiguous?