Applications Using Direct Variation

Key Questions

• What are some examples of direct variation in real life?

  Answer:

  Direct variation in real life.

  Explanation:

  1. A car travels #x# hours with a speed of #"60 km/h"# #-># the distance: #y = 60x#

  2. A man buys #x# bricks that cost #$1.50# each #-># the cost: #y = 1.50x#

  3. A tree grows #x# months by #1/2# meters each month #->#
     the growth: #y = 1/2 x#

  Nghi N. · 142 · Jun 14 2015
• How can you use direct variation to solve real life problems?

  A good question

  Suppose we have to pay up the parking bill at a mall

  ON THE BILL BOARD IT SAYS
  |________|

  |

    FOR A 4  HOUR PARKING   YOU HAVE  TO PAY $3.24
  

  |

    AND UNDER IT A LED SAYS YOU HAVE BEEN HERE FOR (5HRS)
  

  |
  |
  |
  |_________

  now what would you do

  you would use direct variation

  let me make a table

  let x be the cost

  |

  hours parked __ cost

  4                                       |                      $3.24
  

  5 | # x #

  #(3.24* 5)/4 = x #

  solving for #x # you will get #4.05#

  Sidharth · 1 · Jan 8 2015

• What are some examples of direct variation in real life?
• How can you use direct variation to solve real life problems?
• How do you find the direct variation equation if y varies directly as x when #x=4#, #y=48#?
• How do you find the direct variation equation if d varies directly as t when #t=7#, #d=329#?
• What is the constant of proportionality "k" if m is directly proportional to h when #m=461.50#, #h=89.6#?
• How do you find the direct variation equation if z is directly proportional to r when #r=412#, #z=51.5#?
• Wesley earns $6.50 per hour at the bookstore. The total amount of his paycheck varies directly with the number of hours he works. How do you write a direct variation equation for the amount of money y Wesley earns for working x hours?
• The money Sam earns(m) varies directly with the number of hours she baby sits(h). She earns $50 for five hours, how do you write the equation?
• Question #fe135
• Can someone please explain what direct proportion means and give real-life examples?
• The value of y varies directly with x, and y= -8 when x=2. How do you find y when x=3?
• Suppose a varies jointly with #b# and #c# and inversely with #d# and #a = 400# when #b = 16#, #c=5#, and #d = 2#. What's the equation that models the relationship?