A 'Treatise os Algebra. 87

x — 3 x — 7

there will remain —— — i or-, the Number

8 8 '

of Sheep remaining at last. Hence we have ——^— a ; therefore x — 7 — 8s and x — Sa -f- 7 = 47.PROBLEM XVI.

A Son asking bis Father how old he was, the Father, in-Jlead of returning him a direct Answer , tnade the fol-lowing Reply : My Age, says he, 7 Tears ago, was justfour times as great as your Age, at that time, hut 7Tears hence, if you and I live, my Age will then he onlydouble to yours : ’Tis required to find the Age of eachPerson at the Time of asking the Question.

Let x be put to represent the Age of the Son, sevenYears ago, or seven Years before asking the Question;then. the Age of the Father, at that time, was 4X,by the Conditions of the Problem ; but each of theseAges in 14 Years, being increased by 14, it is plain that*-{-14 and 4* -f- 14 will respectively express the twoAges, 7 Years hence; whence, again by the Question,we have 4v-f-14 = 2 x x-|-14 ; from which we get *x— 7 and 4* = 28 ; therefore 74-7—14 and 28 4"

7 = 35 are the two Ages required.

For i 35-7 = iTEIx 4( 35 + 7 = H + 7 x 2.

PROBLEM XVII.

A Market-Woman bought a certain Number os Eggs, atz a Peney, and as many at 3 a Peney, and fold them allout again, at the Rate of 5 for Two-pence ; after whichfr.c found that (instead of making juff her Money again,as she expected) floe had lost 4 Pence by them : What. Number of Eggs had she ?

Let x be the Number of Eggs of each Price, or Sort;

ti.en — will, it is plain, be the Number of Pence which2 >

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