The diagram shows a prism - Edexcel - GCSE Maths - Question 7 - 2021 - Paper 1
Question 7
The diagram shows a prism.
The cross section of the prism is a right-angled triangle.
The base of the triangle has length 5 cm.
The prism has length 25 cm.
The pris... show full transcript
Worked Solution & Example Answer:The diagram shows a prism - Edexcel - GCSE Maths - Question 7 - 2021 - Paper 1
Step 1
Work out the area of the cross section
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The volume of a prism is given by the formula:
V=A×h
where:
V is the volume
A is the area of the cross section
h is the height (or length) of the prism.
Given that the volume is 750 cm³ and the length of the prism is 25 cm,
we can rearrange the formula to find the area of the cross section:
A=hV=25750=30 cm2
Step 2
Find the height of the triangular cross section
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The area of a right-angled triangle is also given by:
A=21×base×height
In this case, the base is 5 cm.
Thus, we can rearrange the formula to find the height (h) of the triangle:
30=21×5×h
Multiplying both sides by 2 gives us:
60=5h
Now, divide both sides by 5:
h=560=12 cm