hey guys. am new here and i hope this site is enough to help me in math. so as u can see am not very good at math and am having 2 hard questions in my assignment hope to find help here. they wana me to use gauss elimination method to solve these 2 word problems. u know matices and stuff :P. so here we go i just need some help in getting the equations see am not very good at math . but specially the word problems. i really cant do anything at word problems. so beside the problems if any one has some advices how to generally solve a word problem i`ll be very thankful.

First word problem.

A chemical manufacturer wants to lease a fleet of 24 railroad tank cars with a combined carrying capacity of 420.000 gallons.. Tank cars with three different carrying capacities are available : 7.000 gallons, 14.000 gallons, and 28.000 gallons. How many each type of tank car should be leased ?.

he also said let X1 be the number of cars with a 7.000 gallon capacity, X2 be the number of cars with 14.000 gallon capacity. and X3 be the number of cars with a 28.000 gallon capacity.

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And here is the second problem.

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as u can see they require me to do steps and everything in detail. and i know they might seems very easy for some of u guys but its my first semister taking math in english and i havn`t taken any math for like 2 years. and am also having a very special problem with the MATH word problem. so dont laugh at me guys and ty for ur help