Question：Which three companies must pay their corporation tax in instalments, assuming a similar level of profits in the previous accounting period?
　　A. E Ltd, a company preparing accounts for the year ended 31 March 2013, with augmented profits of ?1,000,000.
　　B. C Ltd, a company preparing accounts for the 9 months to 31 December 2012 with augmented profits of ?400,000. C Ltd has two associated companies.
　　C. B Ltd, a company preparing accounts for the 10 months to 31 December 2012, with augmented profits of ?1,300,000. B Ltd has no associated companies.
　　D. A Ltd, a company preparing accounts for the year ended 31 December 2012, with augmented profits of ?700,000. A Ltd has one associated company.
　　E. D Ltd, a company preparing accounts for the year ended 31 March 2013, with augmented profits of ?1,600,000.
　　The correct answer is:Companies paying the main rate of corporation tax - B Ltd, C Ltd and D Ltd, must pay by instalments.
　　解析：As A Ltd has one associated company, the upper limit becomes ?1,500,000/2, which is ?750,000. As A Ltd has augmented profits of less than this, it will not pay the main rate of corporation tax.
　　B Ltd prepares accounts for a 10 month period, the upper limit therefore becomes ?1,500,000 x 10/12, which is ?1,250,000. B Ltd's augmented profits are greater than this, so it will pay the main rate of corporation tax.
　　C Ltd prepares accounts for a 9 month period, and has two associated companies, so the upper limit becomes ?1,500,000/3 x 9/12, which is ?375,000. C Ltd's augmented profits are greater than this, so it will pay the main rate of corporation tax.
　　D Ltd has augmented profits above the upper limit, so will pay the main rate of corporation tax.
　　E Ltd has augmented profits below the upper limit, so will not pay the main rate of corporation tax.