Question 769402
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a total of 324 coins of 20 paise and 25 paise make a sum of  Rs 71, then the number of 25 paise coins is.........
Ans:
Let number of 25 paise coins be x
Then number of 20 paise coins = (324 - x)
Value of the 25 paise coins = (25*x) paise
Value of the 20 paise coins = (20*(324 - x)) paise
Total value = Rs 71 = 7100 paise
So we have the equation
{{{25*x + 20*(324 - x) = 7100}}} Solve for x
{{{25*x + 6480 - 20*x = 7100}}}
{{{5*x = 7100 - 6480 = 620}}}
{{{x = 620/5 = 124}}}
No. of 25p coins = 124
No. of 20p coins = 324 - 124 = 200
:)
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