(a) Find the inverse of the matrix:

(a) Find the inverse of the matrix:


(b) Rose bought 20 bags of oranges and 15 bags of mangoes for a total of sh. 9,500. Chumo bought 30 bags of oranges and 20 bags of mangoes for a total of sh. 13,500. If the price of a bag of oranges is X and that of mangoes is y:
(i) Form two equations to represent the information above.
(ii) Hence use the matrix A^-1 above to find the price of one bag of each item.

(c) The price of each bag of oranges was increased by 10% and that of mangoes reduced by 10%. The businesswomen (Rose and Chumo) bought as many oranges and as many mangoes as they bought earlier. Find by matrix method the total cost of oranges and mangoes that the businesswomen bought after the percentage change.

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Wilfykil answered the question on August 20, 2019 at 09:05

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