“Adequate” is a relative term. If the goal of a Yeshiva education is to best prepare children to enter higher education, then only left wing MO Co ed schools offer “adequate” time for secular studies, of course at the detriment of kodesh, where the average graduate doesn’t know which side of a daf gemara is Rashi and which is tosfos.
Kodem kol: it is an undisputed halacha that secular studies bekevius as a study regimen is assur. That is, the pursuit of secular wisdom on a set schedule is unequivocally forbidden by halacha. That is stated in shu”a YD 246. It is an affront to kovod hatorah and it is also bittul Torah. The rishonim who were knowledgeable in these areas learned it be’akrai, here and there, or in the bathroom, as many achronim write.
If so, how can a yeshiva facilitate secular studies as a seder?
The answer is that it’s not leshem limud, for the sake of learning, but rather it is analogous to hiring a person to teach your son a trade – it’s actually a mitzvah!
For some, adequate means enough to make it in business and worldly endeavors, which can be mon-thurs for an hour a day of math and English, stopping at bar mitzvah, with some places only providing English one or two days a week for an hour. That’s how lost chasidim hold
For others it’s determined that a regents diploma is necessary as hishtadlus; this is the position of most non-lakewood litvishe mosdos.
In Lakewood they have English until high school, everyday for a few hours.
So there are 3 mainstream methods, all approved of by gedolei torah and all designed with the intention of limudei chol being a tool necessary on one level or another, but a tool to make parnosa and get along in the world around us. Ish al machanyhu ve’ish al diglo, all of these mahalchim are based beharerei kodesh.
Then there are the maskilim. Those who believe in secular education as a value in it’s own sense. They believe that there is something of value besides what Hashem has given us. Something that must be cultured and grown. Something that is maaviro al daas kono.
מניחים חיי עולם ועוסקים בחיי שעה. Woe is to the ears that behold such words; that greater emphasis should be placed on secular studies or that secular studies have a value in an of themselves to begin with. Chazal say on someone who is able to learn but doesn’t, that he is davar Hashem bazah – he has belittled the word of Hashem. This is the case for any capable young man who abandons the yeshiva for enlightenment elsewhere, casting aside the yoke of heaven for his own enjoyment and desires.
This is but one of the פרי חטאת of modern orthodoxy.