Baking at 425 degrees for 30 minutes is equal to 350 degrees for 45 minutes. Sometimes baking that the lower temperature is required in order to a the item all the way through.
There is no reliable rule for changing cooking times. The dish might not turn
out well at all at a lower temperature. Unless you have a very good reason,
follow the directions in the recipe. These directions have often been arrived at after
many trials.
Short answer is: depends, negligible, and minutes.
Long answer:
The temperature at which you cook things changes /how/ things are cooked not /how long/. The time it takes for heat to move through the food depends on the porosity and density of the food. And temperatures are relatively meaningless for some foods.
Meat. For example, cooking meat at 400 F will caramelize (adding richness) the sugars and proteins faster than at a slightly lower temp. At a point (~310 F) the sugars won't caramelize at all. The same with protein at (~360 F). So if you want good, rich flavor in meat, you need to cook it at a higher temp. In fact, very fine red meats should be cooked at a very high heat (~450 - 475 F), after being seared in a skillet. HOWEVER, there's a flipside. With meat, the higher the temp, the tighter the proteins will be and the less moist (searing retains the juices [i.e., blood, fat, and water] like a bag). The interstitial material (skin-like material that enwraps and flows through the muscle holding the muscle together) is tougher in lower quality and older-animal meats. It needs warm water to loosen it forming a Gelatin. So, ribs should be cooked at a very low temp (preferably ~160, my oven can only do 170 F) for a very long time (6-10 hours). Cooking these at a higher temp will result in unpalatable, dry, chewy, greasy, destined-for-the-trash main course.
Breads. Another common food that uses an oven is bread. Now, there are two kinds of breads, yeast and soda. Yeast breads, obviously, use a microbe to leaven (rise) the mass; likewise, soda breads use chemicals (soda, acid-base, baking powder) to rise the bread. They needed to be treated differently.
Yeast bread. Often low-sugar yeast bread is cooked at a very high (~425 F) temp to give it a nice crusty texture, and it is often glazed with an egg wash to give it color and an extra nice flavor. Again, temperature plays an important role. Low temps will not caramelize the protein in the egg and will not create the delicious, chewy crust.
Sugared yeast breads cannot handle high temps, because the sugars will caramelize (i.e., burn) faster than the rest of mass. So, you get an underdone blackened lump. They are cooked in a medium oven (~325-375 F).
Soda breads are never cooked at a high temp, because they must rise consistently while browning the top properly (they typically have lots of sugar and fat). Oh, that's another thing: fats tend to accelerate browning, and the rate depends on what kind of fat (butter, oil, lard or shortening).
Vegetables. To be short(er), vegetables cook like soda breads.
Bottom Line:
If a recipe says 400 F, use 400 F.
Thinking purely mathematically:
change in temperature of 14.3%, so increase of time by same percentage => 46 minutes (to nearest whole minute). However, this doesn't take into consideration the heat transfer through the food (assumes a linear relationship).
Realistically: Cooking at a lower temperature for slower cooks the food 'deeper', whereas giving the food a quick 'blast' in the oven tends to cook the outside but leave the inside softer/ less cooked. Usually, people aim to cook the food thoroughly, so cook at a low heat for longer. However, particularly when making unusual deserts (at least, in my rather limited experience), sometimes it is preferable to cook quickly at a high temperature.
Basically, cook for roughly 45 minutes, but be prepared for the food to be cooked slightly differently to normal.
If it is something that is not critical for specific timing (like a cake), but instead is something you are roasting (like potatoes), you can convert 45 at 350 to about 35-38 at 400. Just keep an eye on it!
350° for 50-60 minutes equal to, 425° for 35-40 minutes cooked perfectly.
Bunch of idiots on this forum. Your cooking at a higher temp. So if it was 425, you want to cook something that's normally 350, it's going to be less time.
Easy just add 30 + 50 witch equals a hour and 20 minutes.
About 15 minutes.
One hour and 10 minutes.
350° equals 21,000 minutes.
350 degrees Fahrenheit = 176.6 degrees Celsius.
To 350-400 Degrees And About 30 minutes time
1 hour and 46 minutes.
Depends on the weight of the stuffed chicken. At 350, about 20 minutes per pound, plus 15 minutes. A 3 pound chicken would be 1 hr, 15 minutes. The temperature inside the meat/stuffing should reach 165 degrees F.
it takes about 20 minutes, well that's how long it takes me!
one hour and ten minutes
350 degrees Celsius = 662 degrees Fahrenheit
50 Minutes. 60 minutes if you like it more well done.
45 minutes at 350 degrees F
350ºF = 176.67ºC
350 degrees and 60 minutes = 3.5 minutes per pound