Patrick bought some dictionaries and files for $1 474.
The number of dictionaries he bought was 2/3 the number of files he bought.
The cost of a dictionary was $12 more than the cost of a file.
He spent $22 more on dictionaries than on files.
How much did a dictionary cost?
See the following:
You now hve four independent equations in four unknowns. Can you take it from here?
Patrick bought some dictionaries and files for $1 474.
The number of dictionaries he bought was 2/3 the number of files he bought.
The cost of a dictionary was $12 more than the cost of a file.
He spent $22 more on dictionaries than on files.
How much did a dictionary cost? [Find n]
d dictionaries are bought for n dollars each So they will cost a total of nd dollars
f files are bought for m dollars each so they will cost a total of mf dollars
dn + fm = 1474
d= (2/3)f and n=m+12
substituting gives us
23∗f(m+12)+fm=14742f3∗(m+12)+3fm3=14745fm+24f=1474∗3f(5m+24)=1474∗3(1)
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dn=fm+222f3(m+12)=fm+222fm+24f=3fm+6624f−fm=66f(24−m)=66(2)
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(1) divided by (2)
f(5m+24)f(24−m)=3∗147466(5m+24)(24−m)=675m+24=67∗24−67m72m=66∗24m=22 n=22+12=34
the dictionaries cost $34 each