Russell has a collection of 1,200 pennies. Of these pennies, 25% are dated before 1980, 35% are dated from 1980 to 2000, and the rest are dated after 2000. How many pennies in Russell's collection are dated after 2000

The total pennies in Russell's collection dated after 2000 is 800

Step-by-step explanation:

Given

Total Pennies: 1,200

Pennies before 1980: 25%

Pennies between 1980 and 2000: 35%

Required

Number of pennies in Russell's collection are dated after 2000

Let P1 represent pennies dated before 1980

Let P2 represent pennies dated between 1980 and 2000

Let P3 represent pennies dated after 2000

To calculate the number of pennies dated after 2,000. you have to understand that his total collection of pennies is 100%

This means that

P1 + P2 + P3 = 100%

Where P1 = 25% and P2 = 35%.

So, we're solving for P3

By substituting, P1 = 25% and P2 = 35%, we have

25% + 35% + P3 = 100%

60% + P3 = 100%

Make P3 the subject of formula

P3 = 100% - 60%

P3 = 40%

The quantity of pennies dated after 2,000 is then calculated by P3 * Total.

i. e. 40% * 2000

= 0.4 * 2000

= 800

Hence, the total pennies in Russell's collection dated after 2000 is 800

40% dated after 2000