Question 265597
Let {{{x}}} = amount he should invest @ 5.5%
Interest received first year:
{{{.04*4000 + .055x = .045*(4000 + x)}}}
{{{160 + .055x = 180 + .045x}}}
{{{ .01x = 180 - 160}}}
{{{.01x = 20}}}
{{{x = 2000}}}
He must invest $2000 @ 5.5%