Foundation June 2017 Paper 3 Q13
13 A circle is drawn on a centimetre grid.
(a) Draw a tangent to the circle. [1 mark]
(b) Grace works out that the area of the circle is more than 9 cm\(^2\)
Why must this be wrong? [1 mark]
| Answer | Mark | Comments |
|---|---|---|
| Correct tangent drawn | B1 |
Additional guidance
| Accept unruled line if intention is clear | |
| Tangent must be drawn without clear space between line and circle | |
| Ignore square drawn on grid lines from part (b) | |
| Tangent may be drawn as part of a square | B1 |
| Accept tangent which does not extend to both sides of circle | B1 |
| Accept tangent drawn and ignore any radius or diameter drawn | B1 |
| Do not accept tangent and chord drawn together | B0 |
| Answer | Mark | Comments |
|---|---|---|
| Valid reason for the area of the circle or the square around the circle | B1 |
Additional guidance
| The area of the circle stated to be [4.5, 6.2] without incorrect working | B1 |
| Area of circle of radius 1.5 (cm) is 7(.06…) or 7.07 or 7.1 | B1 |
| The square around it is only 9 cm\(^2\) or 9 squares or \(3 \times 3\) square | B1 |
| There aren’t 9 squares in the circle | B1 |
| The circle fits into a 9 cm\(^2\) square or 9 squares or \(3 \times 3\) square | B1 |
| It only covers about [4.5, 6.2] squares | B1 |
| Circle does not (completely) cover nine separate boxes | B1 |
| There is one whole square and 8 part squares in the circle | B1 |
| Because all of the space for 9 is not used up | B1 |
| Calculate radius = 1.6(9…) (cm) or 1.7 (cm) from area of circle 9 (cm\(^2\)) and states radius of circle drawn is smaller | B1 |
| She uses 9 squares that are half in and half out of the circle, she needed to work it out only using the squares inside the circle | B0 |
| Does not fill up the whole square (no reference to 9) | B0 |
| Because the radius is not big enough for it to be 9 | B0 |