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Paul Boncher
2,619 PointsQuiz issue on Device-Specific Media Queries
The quiz after the Device-Specific Media Queries videos has two questions that are very similarly worded...
- A device-pixel-ratio of 2 is equivalent to a resolution value of ________.
and
2.A device-pixel-ratio of 1 is equivalent to a resolution value of ________ dpi.
A uniform standard of answer here would be helpful... Unless I am missing a reason for the questions being phrased as they are. I think the latter (question 2) format would be easiest for the end user, as it takes out a measure of ambiguity from probable answers.
Thanks... again!
James Barnett
39,199 PointsTagging Guil Hernandez to get his thoughts on this
Dean Wiseman
20,901 PointsThe questions in this particular quiz are very difficult to wrap your head around. I find the wording to be very confusing. You end the lesson thinking you understand only to be even more confused when the questions are asked. I spent more time on google afterwards trying to figure out if I was right or wrong. I was right, just reading the questions wrong. Very confusing
4 Answers
John Salzarulo
6,596 PointsI was stumped on this quiz for a while. I kept entering the value "192" instead of "192 dpi". I was so frustrated because I knew it was the right answer and I didn't understand why it was failing. However, I do understand that the unit is just as important as the value. 1,000 dollars vs. 1,000 cents mean very different things.
James Barnett
39,199 PointsI think mentioning in the instructions (don't forget to specify the unit) or something like that. Can help point people in the right direction.
gyuduifgnz
3,673 PointsI still think these questions need revision.
Guil Hernandez
Treehouse TeacherThe first question accepts a dpi or ppi value as the answer. I gave the "dpi" hint in the second question because that's what we used in the lessons.
Guil
Ryan Boone
26,518 PointsQuick follow up, Guil, if a device has a ratio of 2, isn't one device pixel actually represented by four physical pixels?
Guil Hernandez
Treehouse TeacherHi Ryan Boone,
Great question.
A device with a pixel ratio of 2 will display 4 times as many total device pixels. But it still only doubles each CSS pixel. For example, let's break down one of the examples in the link you posted.
If an element is set to 200x300 pixels on a regular screen, a device with a pixel ratio of 2 will need to double it at 400x600 to keep the same physical size. It doubles every pixel, but let's take a look at the total result in device pixels:
200 x 300 = 60,000 device pixels
400 x 600 = 240,000 device pixels
60,000 x 4 = 240,000 device pixels
When we double the CSS pixels it results in 4 times as many device pixels.
Hope this helps :)
Ryan Boone
26,518 PointsGotcha. Confusing, but I understand. Do we REALLY need hi-res screens that bad?
James Barnett
39,199 PointsDo we REALLY need hi-res screens that bad?
If you have an Apple hardware fetish then yes, otherwise probably not, no.
Daniel Muvdi
5,262 Pointshttps://developer.mozilla.org/en-US/docs/Web/CSS/resolution
dpi This unit represents the number of dots per inch. A screen typically contains 72 or 96 dpi; a printed document usually reach much greater dpi. As 1 inch is 2.54 cm, 1dpi ≈ 0.39dpcm. dpcm
so the answer on the first one is 192 if the screen is 96 dpi
and the second one is 96 if the screen is that big.
But this question are not correct because the screen on all devices change constantly so is not a correct value for this questions.
Swapnil Gadge
2,867 PointsYou are right answer of first is 192 dpi.
Rick Rakin
6,531 PointsRick Rakin
6,531 PointsI remember that question and agree.