At a college, 7 out of 10 students work either a full-time or a part-time job in addition to their studies. if 4900 students were involved at college, how many students do not have a full-time or part-time job

1470 students do not have a full-time or part-time job

Step-by-step explanation:

We have a relationship between students who have a part-time job and those who do not. The ratio is 7 out of 10 students.

Then we use this relationship as a conversion factor.

If of 10 students, 7 of them have a job, then of 4900 students, how many of them have a job?

students

Finally, those who do not have a job are:

large crystals result from very slow cooling.

evaporation of water: this would produce an evaporite which is a sedimentary rock. like a salt pan in a desert. not possible to have volcanic rocks originate this way.

crystalization in molten earth: slow cooling over time. (hundreds to millions of years)

crystalization at earth's surface: this results in fast cooling. (a few hours to a few months or years)

crystalization from cooling off hot water: that would be a hydrothermal deposit. while associated with volcanics they are not volcanic rocks themselves and usually occur fairly rapidly.