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Bob has £500 and gives 70% to Edmund and 40% of what is left to George. Work out how much money each person has.

Follow the order of the question- take 70% of £500 = 7 times 10% of £500 = 7x£50 = £350. Therefore Edmund has £350. Bob now has £500-£350=£150. This needs to be split between Bob and George. Using the same m...
DB
Answered by Daniel B. • Maths tutor
2175 Views

A cuboid has sides such that the longest side is two units more than the shortest side, and the middle length side is one unit longer than the shortest side. The total surface area of the cuboid is 52 units². Calculate the length of the shortest side.

The sides of the cuboid are as follows: x, x+1 and x+2. Total surface area of a cuboid is the area of each surface added together. Therefore 2x(x+2)+2x(x+1)+2(x+2)(x+1)= 52 units². 2x²+4x+2x²+2x+2x²+6x+4= 52...
SS
Answered by Sabina S. • Maths tutor
3710 Views

Integrate x^2e^x with respect to x between the limits of x=5 and x=0.

This question is to test integration by parts. First let u=x 2 and u'=2x as a result, and v'=e x and so v=e x too. Then use the by parts formula to express the integral as x 2 e x ​​​​​​​-2(integral of):(xe ...
AA
Answered by Alex A. • Maths tutor
6431 Views

Make n the subject of the formula: m = 5n - 21

The answer is: n = (m + 21)/5 How did we get this? Right now, the equation is written in the form where m is the subject. We want to rearrange this so that n is the subject of the formula. The formula should...
JC
Answered by Jabin C. • Maths tutor
20768 Views

What is the turning point on the curve f(x) = 2x^2 - 2x + 4

df/dx = 4x - 2 turning point when differential = 0 ==> 4x = 2 hence; x = 0.5 When x = 0.5 f(x) is equal to (substitute) 3.5 hence the turning point is at (0.5,3.5)
DT
Answered by David T. • Maths tutor
6180 Views