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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 = 549 amps and R=93.6 ohms, both measurements are correct to 3 significant figures. By considering bounds calculate the voltage, V, to a suitable degree of accuracy. Give a reason for your answer.

**Question 2:**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 = 793 Newtons and A=28.9m

^{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 3:**An alloy has a mass of 540g and a volume of 70cm

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

**Question 4:**The length of a rectangle is 145cm correct to the nearest cm. The width of the rectangle is 70cm correct to the nearest 5cm. Calculate the upper and lower bounds of the area of the rectangle. Give your answers to 3 decimal places.

**Question 5:**A water tank holds 26.4 litres of water correct to 3 significant figures. An empty cup can hold 71 centilitres of water correct to 2 significant figures. Calculate the maximum and minimum number of cups of water that can be completely filled from the water tank.

**Question 6:**A tourist travels 120km at a speed of 30km/h. The distance is correct to the nearest 10km. The speed is correct to the nearest 5km/h. Calculate the upper and lower bounds of the time taken. Give your answers to 3 decimal places.

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**Question 1:**Upper bound = 51,460.675 volts, lower bound = 51,312.175 volts V=51,000 volts correct to 2 s.f. because the upper and lower bounds are equal when rounded to this accuracy

**Question 2:**Upper bound = 27.50433N/m

^{2}, lower bound = 27.37478N/m

^{2}P=30N/m

^{2}correct to 1 s.f. because the upper and lower bounds are equal when rounded to this accuracy

**Question 3:**Upper bound = 8.074g/cm

^{3}, lower bound = 7.379g/cm

^{3}

**Question 4:**Upper bound = 10,548.750cm, lower bound = 9,753.750cm

**Question 5:**Upper bound = 37 cups, lower bound = 36 cups

**Question 6:**Upper bound = 4.545hrs, lower bound = 3.538hrs

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