FSTP SAMPLE ASSESSMENT 1 TASK 2C HELP

I know I should know the answer but for the life of me I just can not work it out..mind has gone blank.
It asks to work out the closing inventory value....I know the actual answer is £4720 but I can not work out how to get to that figure!!!
I have worked out the rest
Task 2a
Assest = £19650
Liabilites = £5560
Capital = £14090
Task 2b
During the year ended 31 March 20x7, sales of £63,900 were made. The trader operates a gross sales margin of 25%
Calculate the cost of goods sold for the year ended 31 March 20x7
=£47925
Task 2c
Purchases for the year were £46,795
Calculate the value of closing inventory
It asks to work out the closing inventory value....I know the actual answer is £4720 but I can not work out how to get to that figure!!!
I have worked out the rest
Task 2a
Assest = £19650
Liabilites = £5560
Capital = £14090
Task 2b
During the year ended 31 March 20x7, sales of £63,900 were made. The trader operates a gross sales margin of 25%
Calculate the cost of goods sold for the year ended 31 March 20x7
=£47925
Task 2c
Purchases for the year were £46,795
Calculate the value of closing inventory
0
Comments
Take that, add purchases, deduct cost of goods sold and you should get to the answer (assuming no complicating factors).
Opening inventory 5850 + Purchases 46795- cos 47925=4720