We need (x-h)^2 + (y-k)^2 = r^2
h = 4, k = 0 and r = 2/3
Take it from here.
The ratio is 9:52. Meaning there is 9 crabs in the tide pool compared to all other invertebrates in the tide pool (including crabs). Crabs are also probably higher on the food chain because there is less of them, meaning they require more food then the other invertebrates.
Hope this helps!
1/10x + 6 = 2/5x
6 = 2/5x - 1/10x
6 = 4/10x - 1/10x
6 = 3/10x
6 / (3/10) = x
6 * 10/3 = x
60/3 = x
20 = x <=== the gas tank can hold 20 gallons
The # halfway in between 21 and 63 is 42.
