Theory question 106
Commercial Arithmetic(a) A manufacturing company requires 3 hours of direct labour to process every N87.00 worth of raw materials. If the company uses N30,450.00 worth of raw materials, what amount should it budget for direct labour at N18.25 per hour?
(b) An investor invested Nx in bank M at the rate of 6% simple interest per annum and N y in bank N at the rate of 8 % simple interest per annum. If a total of N8,000,000.00 was invested in two banks and the investor recieved a total of N2,320,000.00 as interest from two banks after 4 years, calculate the: (i) values of x and y; (ii) interest paid by the second bank.
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(a) 30 450 ÷ 87 = 350 lots of N87; hours = 350 × 3 = 1050 h
Budget = 1050 × 18.25 = N19,162.50
(b)(i) x + y = 8 000 000; 0.06 × 4x + 0.08 × 4y = 2 320 000 → 0.24x + 0.32y = 2 320 000
0.24(8 000 000 − y) + 0.32y = 2 320 000 → 0.08y = 400 000 → y = N5,000,000, x = N3,000,000
(ii) Interest from bank N = 0.32 × 5 000 000 = N1,600,000
Set up one equation for the money and one for the interest.