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**Question 1:**The formula to calculate voltage, V, (measured in volts) is V = IR where I is the current (in amps) and R is the resistance (in ohms).

I = 25.2 amps correct to 1 decimal place and V=44.56 volts correct to 2 decimal places. By considering bounds calculate the resistance, R, to a suitable degree of accuracy. Give a reason for your answer.

**Question 2:**An alloy has a mass of 35kg and a density of 5,100kg/m

^{3}. The density is correct to the nearest 10kg. The mass is correct to the nearest 5kg. Calculate the upper and lower bounds of the volume of the alloy. Give your answers to 3 decimal places.

**Question 3:**A crate is in the shape of a cuboid. It has a square base 2,730 millimetres wide, rounded to the nearest 10mm. The crate has a height of 1205 millimetres rounded to the nearest 5mm. Calculate the upper and lower bounds of the volume of the crate, in cubic metres. Give your answers to 3 decimal places.

**Question 4:**A tourist travels 45.5km at a speed of 3.86km/h. The distance is correct to 1 decimal place. The speed is correct to 2 decimal places. Calculate the upper and lower bounds of the time taken. Give your answers to 3 decimal places.

**Question 5:**The formula to calculate pressure, P, (in Newtons/metre

^{2}) is P =

A

F

where F is the force in Newtons and A is the area in metres^{2}.

F = 419 Newtons and A=87.7m

^{2}, both measurements are correct to 3 significant figures. By considering bounds calculate the pressure, P, to a suitable degree of accuracy. Give a reason for your answer.

**Question 6:**The length of a rectangle is 962cm correct to the nearest cm. The width of the rectangle is 5cm correct to the nearest 5cm. Calculate the upper and lower bounds of the area of the rectangle. Give your answers to 3 decimal places.

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**Question 1:**Upper bound = 1.77197 ohms, lower bound = 1.76455 ohms R=1.8 ohms correct to 2 s.f. because the upper and lower bounds are equal when rounded to this accuracy

**Question 2:**Upper bound = 0.007m

^{3}, lower bound = 0.006m

^{3}

**Question 3:**Upper bound = 9.032m

^{3}, lower bound = 8.929m

^{3}

**Question 4:**Upper bound = 11.816km/h, lower bound = 11.759km/h

**Question 5:**Upper bound = 4.78608N/m

^{2}, lower bound = 4.76923N/m

^{2}P=4.8N/m

^{2}correct to 2 s.f. because the upper and lower bounds are equal when rounded to this accuracy

**Question 6:**Upper bound = 7,218.750cm, lower bound = 2,403.750cm

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