For the next RSM Award ceremony, it was decided to decrease the length of the main poster by 12% and to increase its width by 15%. By how many percent did the poster's area change? Did it increase or decrease?

Respuesta :

Limosa

Answer:

The Area of the poster has changed by +1.2%

The area has increased

Step-by-step explanation:

Lets take the initial length of the poster as [tex]x[/tex], and

Initial width of the poster as [tex]y[/tex].

Therefore,

Initial area of the poster = [tex]xy[/tex]

Now after the changes to length and with:

length of the poster = [tex]x-\frac{12}{100} x[/tex]

                                  = [tex]\frac{88}{100} x[/tex]

width of the poster   = [tex]y+\frac{15}{100} y[/tex]

                                  = [tex]\frac{115}{100} y[/tex]

New Area of the poster = [tex]\frac{88}{100} x*\frac{115}{100} y[/tex]

=[tex]\frac{88*115}{100*100} *xy[/tex]

=[tex]\frac{10,120}{10,000} *xy[/tex]

=[tex]1.012*xy[/tex]

Change in Area = Area after change - Initial Area

=[tex]1.012*xy-xy[/tex]

=[tex]0.012*xy[/tex]

Percentage area change = [Change in Area / Initial Area]*100

=[tex]\frac{0.012xy}{xy} *100[/tex]

=[tex]1.2[/tex]%

The area has increased

Answer:

An increace of 1.2%

Step-by-step explanation:

hope this is right