Can you solve the maths problem that police officers struggled with?

When 10-year-old Lena Drapers contacted her local police department on Facebook to help with her maths problems, she never thought they would actually respond.

The Marion Police Department, Ohio, answered Lena’s call for help, and at first it went swimmingly

I’m having trouble with my homework. Could you help me?

The first one was a straightforward equation:

(8+29)x15

The police instructed Molly to 'do the numbers in the parenthesis first so in essence it would be 37x15'.

The answer was 555.

But the second equation was a little bit difficult…

(90+27)+(29+15)x2

The police instructed her to:

Take the answer from the first parenthesis plus the answer from the second parenthesis and multiply that answer times two.

Right.

Doing that would give you 322.

Except that gave Lena (and her mum Molly) the wrong answer.

Can you tell how the police instructed her incorrectly?

We'll give you a moment.

(You can scroll down once you've got the answer, and if not, to get it...)

When a friend of Lena’s mum confirmed that she got the wrong answer Lena told her mum, who didn’t believe her.

Molly told ABC News:

[I] asked for a screen shot. I thought it was pretty funny. And I love that they went ahead with it.

To their credit, the police department were good sports, and wrote (in a post that no longer appears on Facebook):

Hoping it is truly the thought that counts since apparently I cannot. Especially since the answer was wrong, it was very nice for Molly to acknowledge our attempt to help her daughter with some math homework.

For those who want to know...

(90+27)+(29+15)x2

HT ABC News

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