[5pace]

There may be similar questions here but I wasn't sure where to start my search as I do not have an extensive chemistry background.
I'm currently trying to solve a problem at work with mixing chelated calcium, magnesium sulfate heptahydrate and water to get a desired concentration solution. I'm sure this isn't a difficult question but I could really use some guidance on how to go about solving this.
The chelated calcium is 9% concentration (and should be nonreactive since chelated?), the magnesium sulfate heptahydrate states 9.8% Mg, 12.9% S and I want to get an amount per gallon of the two compounds to achieve a solution of 3.2% Ca and 1.2% Mg.
If any of you can help me out or point me in the right direction to solve this myself it would be greatly appreciated!

Best,
5pace

[AWK]

Such calculations are based on mass balance. For exact calculations, you need densities of solutions. Otherwise, you may obtain concentrations with 5-10 % error (my guess). You should show your approach!
By the way, the stability of rather weak calcium chelates strongly depends on even tiny changes of pH.