# Math

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I need help with these three problems. I cant figure them out.

3. The difference of two numbers is tripled. The result is decreased by 1. If the lesser of the two numbers is 4 the result is 8.3. Find the greater number.

4. A number increased by 21 is ewuivalent to half the number increased by 18.5. find the number.

11. Kerry comutes 60 mi per day. If she drives 30 mi/h during the morning rush and returns over the same route at 50 mi/h how much time does she typically spend commuting each day.

• Math - ,

First set up problems to solve each one assiging variables to each unknown. Remember, you need the same number of problems as you have variables.

• Math - ,

Convert the words into one or more mathematical equations. I'll get you going on the first one.

"The difference of two numbers ..."
x - y

"... is tripled."
(x - y) * 3
or equivalently
3(x - y)

"The result is decreased by 1."
3(x - y) - 1

"If the lesser of the two numbers is 4 ..."
y = 4, so we have
3(x - 4) - 1

"the result is 8.3."
3(x - 4) - 1 = 8.3

"Find the greater number. "

solve the above for x.