you have 16 coins that are heads up and 18 coins that are tails up. After you add some coins that are tail up the ratio of heads up to tails up is 1:1.5. How many are tails up?

Heads up stay at 16

Ratio of 1:1.5 gives 16*1.5/1 = 24
Tails up original count = 18
Tails up added = 24-16 = 8

To find out how many coins are tails up, let's start by calculating the ratio of heads up to tails up coins.

We know that initially, there are 16 heads up coins and 18 tails up coins. So the initial ratio of heads up to tails up coins is 16/18.

Now, let's assume we add 'x' coins that are tails up. After adding these coins, the new ratio of heads up to tails up coins is 1:1.5.

To calculate the new ratio, we need to consider the initial number of coins plus the new coins we're adding. Since we're only adding tails up coins, the number of heads up coins will remain 16.

Therefore, the new ratio can be expressed as (16)/(18 + x) = 1/1.5.

To solve this equation, we can cross-multiply:

1.5 × 16 = 18 + x.

24 = 18 + x.

Subtracting 18 from both sides:

24 - 18 = x,

6 = x.

So, we have added 6 coins that are tails up.

Now, to find out how many coins are tails up, we can add the initial number of tails up coins (18) to the new coins we added (6):

18 + 6 = 24.

Therefore, there are 24 coins that are tails up.