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Julia wants to buy a new computer. 20% VAT is added to the price of the computer so that she now has to pay £300. What was the original price of the computer without VAT.

First the most important aspect to recognize is that the original price of the computer is 100%, the additional 20% of VAT makes the total value of the computer change to 120%. Therefore, the 120% = £300....

Answered by Patricio S. • Maths tutor

4962 Views

Differentiate with respect to x, y = (x^3)*ln(2x)

By product rule,
dy/dx = x³(2/2x) + 3x²ln(2x)
= x²(1 + 3ln(2x))

Answered by Thomas M. • Maths tutor

6410 Views

John ran a race at his school. The course was measured at 450m correct to 2sf and his time was given at 62 econds to the nearest second. Calculate the difference between his maximum and minimum possible average speed. Round you answer to 3sf.

Upper bound for distance: 455mLower bound for distance: 445mUpper bound for time: 62.5sLower bound for time: 61.5sSpeed = Distance/timeMaximum possible average speed would be the longest distance divided ...

Answered by Gideon E. • Maths tutor

3888 Views

a) Point A(6,7,2) lies on l1. Point B(9,16,5) also lies on l1. Find the distance between these two points. b) l2 lies in the same z plane as l1 and crosses l1 at A and is perpendicular to l1. Express l2 in vector form.

a) Distance between two points ((x2- x1)^2 + (y2-y1)^2)^1/2Substitute in values to find distance.b) Write out l1 in vector form using info from points A and B.Use knowledge of scalar product to construct ...

Answered by Adam N. • Maths tutor

2937 Views

The perimeter of a right angled triangle is 105cm. The lengths of its sides are in the ratio of 2:6:7. Work out the area of the triangle.

Add up ratios: 2+6+7=15Divide perimeter by ratio total, to figure out how big the scale of the triangle is: 105/15=7Multiply each separate figure in the ratio by the scale factor (7): 2x7 : 6x7 : 7x714 : ...

Answered by Megan H. • Maths tutor

3952 Views