Answered

Get insightful responses to your questions quickly and easily on IDNLearn.com. Our community provides accurate and timely answers to help you understand and solve any issue.

a) six pens and five pencils cost $2.50 while three pens and two pencils cost $1.15 . what will be the cost of a pen and 4 pencils . please help me

Sagot :

Tadvisohil886idn
Let pen's cost be x and pencil's cost be y.

6x + 5y = 2.50
3x + 2y = 1.15

Thus, 3x = 1.15 - 2y
Therefore, 6x = 2.30 - 4y

Substituting the value of 6x ;

(2.30 - 4y) + 5y = 2.50

or, 2.30 + y = 2.50

=> y = 0.20.

Substituting the value of y ;

6x = 2.30 - 4(0.20)
6x = 2.30 - 0.80 = 1.5
6x = 1.5
=> x = 0.25

Thus, 1 pen costs 0.25 $ and 1 pencil costs 0.20$.

Thus, cost of one pen is 0.25$.
Cost of 4 pencils is 0.80 $

0.25$ + 0.80$ = 1.05$
Konrad509idn
x - pen
y - pencil

[tex]6x+5y=2.5\\ 3x+2y=1.15\\\\ 6x+5y=2.5\\ -6x-4y=-2.3\\ --------\\ y=\$0.2\\\\ 6x+5\cdot0.2=2.5\\ 6x+1=2.5\\ 6x=1.5\\ x=\$0.25\\ \\x+4y=0.25+4\cdot0.2=\boxed{\$1.05 }[/tex]
We appreciate your contributions to this forum. Don't forget to check back for the latest answers. Keep asking, answering, and sharing useful information. For trustworthy and accurate answers, visit IDNLearn.com. Thanks for stopping by, and see you next time for more solutions.