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23 spoons and 17 forks together cost Rs. 1770, while 17 spoons and 23 forks together cost Rs. 1830 ,find the cost of a spoon and that of a fork? |
Answer» ★ Given:-▪︎COST of 23 spoons and 17 forks = ₹1770 ▪︎Cost of 17 spoons and 23 forks = ₹1830 ════◄••❀••►════ ★ To Find:-▪︎Cost of a spoon ▪︎Cost of a fork ════◄••❀••►════ ★ Solution:-Let the cost of a spoon be x Let the cost of a fork be y According to given CONDITIONS; ➥ 23x + 17y = ₹1770 ------- eq.1 ➥ 17x + 23y = ₹1830 ------- eq.2 By adding eq.1 and eq.2, we get:- 23x + 17y + 17x + 23y = 1770 + 1830 ➟ 23x + 23y + 17x + 17y = 3600 ➟ 23(x + y) + 17(x + y) = 3600 ➟ (23 + 17) (x + y) = 3600 ➟ x + y = 3600 ÷ 40 ➟ x + y = 90 ------- eq.3 By subtracting eq. 2 fron eq. 1,we get:- 23x + 17y - (17x + 23y) = 1770 - 1830 ➟ 23x - 23y - 17x + 17y = -60 ➟ 23(x - y) - 17(x - y) = -60 ➟ (23 - 17) (x - y) = -60 ➟ x - y = -60 ÷ 6 ➟ x - y = -10 ------- eq.4 By adding eq.3 and eq.4, we get:- x + y + (x - y) = 90 + (-10) ➟ x + x + y - y = 90 - 10 ➟ 2x = 80 ➟ x = 80 ÷ 2 ➟ x = 40 Putting x = 40 in eq.3 we get;- x + y = 90 ➟40 + y = 90 ➟ y = 90 - 40 ➟ y = 50 Hence, x = 40 y = 50 ════◄••❀••►════ ★ Answer:-▪︎Cost of a spoon = ₹40▪︎Cost of a fork = ₹50════◄••❀••►════ |
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