A maths problem aimed at 12-year-olds has left a parent stumped and asking for help online.
Eager to assist their child in working out the answer, the parent, who appears to be from the US, posted the question on the ‘HomeworkHelp’ subreddit on the Reddit discussion forum.
The problem, which was included on a worksheet for ‘7th Grade Advanced Placement math’ – year eight in UK secondary schools – showed a square and an equilateral triangle.
Each edge of the square was equivalent to 2 1/8x + 30 while each edge of the triangle was labelled 5 1/3x.
The question read: ‘The square and the equilateral triangle below have the same perimeter. Find the value of x. Then find the perimeter of each shape.’
The parent and child duo had managed to complete the first step, which was to come up an equation that would eventually lead students to the right answer.
Having written ‘(2 1/8x + 30)4 = (5 1/3x)3’, the parent asked fellow Reddit users: ‘We are pretty sure the equation is appropriate, but any path we take to isolate x gives the wrong answer. Can somebody please walk us through the proper steps to solve for x?’
A number of people attempted to solve the problem – but not all were successful.
A parent, who appears to be from the US, posted this maths problem on the ‘HomeworkHelp’ subreddit on the Reddit discussion forum.
Most appeared to understand that, since the perimeter of the square and triangle were the same, it was first necessary to solve the simultaneous equation.
A perimeter is calculated by adding up the length of every side of a shape.
Given that all the sides of a square are the same length and all sides of an equilateral triangle are equal too, it was clear that the equation for the perimeter of the square was (2 1/8x + 30)4.
Similarly, the perimeter of the triangle could be determined using the equation (5 1/3x)3 – just as the parent and child who posted the maths question had said.
Because students had been told that the two perimeters were equal, it was possible to solve for x by putting the equations together.
This gave: (2 1/8x + 30)4 = (5 1/3x)3. That equation could then be simplified as: 8.5x + 120 = 16x.
From there, the equation was modified to 120 = 16x- 8.5x, which, in turn, led to 120 = 7.5 x.
The next step was to divide both sides by 7.5 to determine the value of x: 120 / 7.5 = x.
A parent, who appears to be from the US, posted this maths problem on the ‘HomeworkHelp’ subreddit on the Reddit discussion forum.
Therefore, x was equal to 16. It was possible to check the answer by substituting x in the equation for 16.
And, from there, it was simple to work out the perimeter of each shape.
To find out the length of each side of the square it was: (2 1/8 x 16)+ 30 = 64.
The perimeter, therefore, was 64 x 4 = 256.
And, to work out the perimeter of the triangle, it was (5 1/3 x 16)3 = 3 x 85.333 = 256.
It comes after several people found themselves struggling to solve maths problems left on a GCSE paper from an exam earlier this year.
After revising long and hard for their exams over the past couple of months, British teenagers finally received their GCSE results on August 21.
It marked a tense occasion for both students and their parents – who would’ve had to refresh their numeracy and literacy skills themselves to help children study.
From year nine onwards, teenagers are taught more challenging mathematical concepts such as algebra, geometry, fractions, ratio, logic and statistics.
Many parents, however, would have forgotten the basics by the time their offspring’s exams came around.
So, how would you fare if faced with GCSE questions that 16-year-olds have to answer?
The Daily Mail plucked some real questions from taken from a 2024 OCR non-calculator higher paper.
Here are 12 questions from a GCSE Higher Tier OCR mathematics exam. You may need a pen and paper…
1. Work out 1.2 ÷ 0.03
2. Solve the following problem:
3 (A) y is directly proportional to x. Write down the percentage increase in y when x is increased by 100%
(B) z is inversely proportional to x. Write down the percentage decrease in z when x is increased by 100%.
4. Find the value of a in the problem below:
5. Solve the inequality below:
6. Sasha invests £1000 at a rate of 5% per year compound interest. Sasha says: ‘After one year, my investment will get £50 in interest and will be worth £1050. Therefore, after two years, my investment will get another £50 in interest and will be worth £1100.’ Is Sasha correct? Give a reason for your answer
7. Expand and simplify: (X+3)(4X+1)(X-2)
8. Find the nth term in the following sequence:
9. Work out the perimeter of the shape below:
10. Two prisms, A and B, are mathematically similar. The ratio of the volume of prism A to the volume of prism B is 8 : 27. The height of prism A is 6 cm. Work out the height of prism B.
THE ANSWERS
1. 40
2. 1800 final answer and 200 and 9 shown in workings out
3. (A) 100 (B) 50
4. 8
5.
6. No AND correct valid reason or correct supporting values e.g. The value of the interest changes each year as the amount grows. It is exponential growth. Compound interest means the interest grows each year
7.
8.
9.
10. 9
