Cary collected a total of 400 pennies and dimes. 80% of them

are pennies. After donating some pennies, 50% of the

remaining coins were pennies. How many pennies did Cary

donate?

pennies

Number of pennies Cary donated = 240

Step-by-step explanation:

According to the question,

Pennies + Dimes = 800

number of pennies = 80% of 400 = = 320

number of dimes = 400 - 32 = 80

then Cary donated some pennies.

Let us assume that Cary donated = x pennies

After donating some pennies, 50% of the remaining coins were pennies.

which can be written as;

320 - x =

320 - x = 0.5 (400-x)

x = 240

So, number of pennies donated = 240

the discriminant is 64 + 4*1*12 = 112

this is prime.

step-by-step explanation: