Question

A jar contains 50 coins, all either 2 or 5 cents. the total value of the coins is 1.87. how many 2 cents coins are there?

Answer 1

Question:

A jar contains 50 coins, all either 2 or 5 cents. the total value of the coins is 1.87. how many 2 cents coins are there?

Answer:

no of 2 cents coins =21

no of 2 cents coins =21no of 5 cents coins =29

Step-by-step explanation:

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)

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1x+1y=50

0.02x+0.05y=1.87

we'll use substitution. After moving 1*y to the right, we get:

1×x=50–1×y or x=50/1–1×y/1

and simplify: So, we know that y=29.

Since x=50/1–1×y/1

so x=21

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no of 2 cents coins =21

no of 2 cents coins =21no of 5 cents coins =29