Karen Morrison and Nick Hamshaw Solutions for Exercise 6: Exercise 13.6

The graph is a conversion graph for kilometres and pounds. Check whether the given conversion is correct or not? If it is incorrect, find the correct value.

$20 \mathrm{pounds}=9 \mathrm{kg}$

The graph shows the conversion between $\mathrm{UK}$ pounds and $\mathrm{US}$ dollars, as shown on a particular website in February, $2011$. Use the graph to convert $25$ pounds to dollars.

The graph shows the conversion between $\mathrm{UK}$ pounds and $\mathrm{US}$ dollars, as shown on a particular website in February, $2011$. Use the graph to convert $52$ pounds to dollars.

The graph shows the conversion between $\mathrm{UK}$ pounds and $\mathrm{US}$ dollars, as shown on a particular website in February, $2011$. Use the graph to convert $80$ dollars to pounds.

The graph shows the conversion between $\mathrm{UK}$ pounds and $\mathrm{US}$ dollars, as shown on a particular website in February, $2011$. Use the graph to convert $65$ dollars to pounds.

The cooking time (in minutes) for a joint of meat (in kilograms) can be calculated by multiplying the mass of the joint by $40$ and then adding $30 \mathrm{minutes}$. The graph shows the cooking time for different masses of meat. If a joint of this meat has a mass of $3.4 \mathrm{kg}$ approximately how long should it be cooked?

The cooking time (in minutes) for a joint of meat (in kilograms) can be calculated by multiplying the mass of the joint by $40$ and then adding $30 \mathrm{minutes}$. The graph shows the cooking time for different masses of meat. If a joint of meat is to be cooked for $220 \mathrm{minutes}$, approximately how much is its mass?

The cooking time (in minutes) for a joint of meat (in kilograms) can be calculated by multiplying the mass of the joint by $40$ and then adding $30 \mathrm{minutes}$. The graph shows the cooking time for different masses of meat. By calculating the mass of a piece of meat that takes only $25 \mathrm{minutes}$ to cook, explain carefully why it is not possible to use this graph for every possible joint of meat.