Question 936396
let  x be the no of 2 cents coins and y be the no of 5 cents coins
  total no of coins  =50
  x+y= 50 -------------eq(1)

The total value of the coins is $1.87
  x*0.02+y*0.05 = 1.87 .........eq(2)
*[invoke linear_substitution "x", "y", 1, 1, 50, 0.02, 0.05, 1.87]
  no of 2 cents coins  =21
 no of 5 cents coins  =29