math word problem: if jill takes a pill every 3 days and joe takes it every 4 for 65 days how many times will they take the pills together

Jill will have taken 21 in 65 days because 65 divided by 3 is 21.6666666667.

Joe will have taken 16 in 65 days because 65 divided by 4 is 16.25.

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.