The phrase "a certain ratio of" is correct and usable in written English.
It can be used when discussing proportions or comparisons between quantities in various contexts, such as mathematics, science, or cooking.
Example: "To achieve the desired flavor, you should mix a certain ratio of salt to sugar in the recipe."
Alternatives: "a specific proportion of" or "a defined ratio of".
But the basic idea is that to be a tax-free deal in this circumstance, there had to be a certain ratio of cash to stock.
He acknowledged, however, that the terms of the bank loans require the group to meet certain performance requirements, including a certain ratio of profit to debt.
By this measure -- a certain ratio of red, green and blue in the pixel -- the skins of all races look essentially the same.
Some states have laws requiring a certain ratio of nurses to patients in particular health-care sectors, but most do not regulate the issue at all.
"The rule provides that a certain ratio of units within a condominium must be occupied by their owners," Mr. Sherman said, adding that this was mainly because "investor-owned units tend to result in higher rates of foreclosure".
This isn't the only possible way to do things; in Germany's extensive vocational education system, employers are obliged by law to set aside a certain ratio of apprenticeships, so students will have someplace to go after they graduate.
This article also applies the idea of mixing modulation symbols of EM and standard Gray mapping at a certain ratio, original idea of which was first introduced in [17, 21].
Perron and colleagues guessed that a certain ratio between rates of incision and soil creep acts as a "tipping point" for the creation of river branches.
There should be a certain ratio between the inventory of oil tanks and the blending capacity of oil tanks.
It is demonstrated analytically and numerically that these properties are achieved by choosing a specific spatial rotational phase between successive cams, and by choosing a certain ratio between the number of wavelengths and cams along the device.
However, until now, the biological significance of the presence of a certain ratio between HAP and WH in bone is unclear.
