问题标题：
一道GMAT数学题ThisyearHenrywillsaveacertainamountofhisincome,andhewillspendtherest.NextyearHenrywillhavenoincome,butforeachdollarthathesavesthisyear,hewillhave1+rdollarsavailabletospend.Intermsofr,whatfract
问题描述：
一道GMAT数学题
ThisyearHenrywillsaveacertainamountofhis
income,andhewillspendtherest.NextyearHenry
willhavenoincome,butforeachdollarthathesaves
thisyear,hewillhave1+rdollarsavailabletospend.
Intermsofr,whatfractionofhisincomeshouldHenry
savethisyearsothatnextyeartheamounthehas
availabletospendwillbeequaltohalftheamountthat
hespendsthisyear?
foreachdollarthathesaves
thisyear,hewillhave1+rdollarsavailabletospend.
完全不懂这句话……求解!
贾丽芹回答：
设今年存了x花了y
则明年取出来x（1+r）
令x（1+r）=y/2则得出y=2x（1+r）
要求的fraction=x/x+y=x/x(2r+3)=1/2r+3
点击显示
数学推荐
热门数学推荐