SOLUTION: Set up an inequality and solve it. Be sure to label clearly what the variable represents. If three-fourths of a number is 21 less than two-fifths of the number, what is the number?
Algebra.Com
Question 362079: Set up an inequality and solve it. Be sure to label clearly what the variable represents. If three-fourths of a number is 21 less than two-fifths of the number, what is the number?
Answer by checkley77(12844) (Show Source): You can put this solution on YOUR website!
3/4X=2/5x-21
3X/4=2X/5-21
3X/4-2X/5=-21
(5*3X-4*2X)/4*5=-21
(15X-8X)/20=-21
7X/20=-21 CROSS MULTIPLY.
7X=-21*20
7X=-420
X=-420/7
X=-60 ANS.
PROOF:
3/4*-60=2/5*-60-21
-180/4=-120/5-21
-45=-24-21
-45=-45
RELATED QUESTIONS
Solve the following problem algebraically. That is, set up an equation and solve it. Be... (answered by nerdybill)
Solve the following problem algebraically. That is, set up an equation and solve it. Be... (answered by robertb)
it costs $3 a day to rent a mario brothers game. it costs $25 to buy it. what is the... (answered by josmiceli,haileytucki,richard1234)
Three-fourths of number is negative eighty- one. What is the number?
a. Write an... (answered by jorel555)
find three consecutive odd integers such that twice the sum of the first and third... (answered by Theo)
Would someone please help me set up this word problem with the right formula, and show me (answered by tutor_paul)
Write the word statement as an equation. Use x as the variable. Find the solution from... (answered by Fombitz)
1)Write the following as an equation, using x for the unknown number.Then solve.... (answered by ewatrrr)
What example from my line of work ( catering ) or daily life can be expressed as an... (answered by ankor@dixie-net.com)