Question 19 of the 2011 maths Paper A is much more of a ‘level 5’ type question as it involves interpreting a line graph. For the most part children in primary school will use and interpret bar graphs where the data is discreet i.e. each column is totally separate. With a line graph the intermediate values have meaning, so a reading can be taken from anywhere along the line. The first thing to do is to work out how the axes have been numbered. The vertical axis is labelled in hundreds, with intermediate marks made for each fifty. The horizontal axis is labelled in tens, with intermediate marks made for each two. It’s not a bad idea to write the missing values in on the axes. To find the answer to 19a, ‘At what distance were exactly half the children still cycling?’ a quick calculation to find half of 500 is needed: i.e. 250. Then find 250 on the vertical axis and move across until the line is met. It might be a good idea to place a small cross at this point. Then read the horizontal axis at this point, perhaps by moving a finger down or using a ruler, from the cross to the horizontal axes. The reading  should be  16. To find the answer to 19b the reverse process of the above is best. Start on the horizontal axis at 20 and move up until the line is met. Make a small cross. Then move across to the vertical axis, perhaps using a ruler. It is about three quarters of the way between 150 and 200. Half way between would be 175 and half way from 175 to 200 would be about 187, within the acceptable range of correct answers. Go to Maths SAT Paper A 2011 question 19 Go to Maths SAT Paper A 2011 answer 19