A sum of money at simple interest doubles in 7 years. It will be come four times in

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

A sum of money at simple interest doubles in 7 years. It will be come four times in

A90 years

B18 years

C38 years

D21 years

All DiscussionsClick here to write answer

Answer is : 21 years Explanation: let amount be x. Case 1 : amount becomes 2x => simple interest = x Case 2 : amount becomes 4x => simple interest = 3x $SI= \frac{P \times R \times T}{100}$ i.e., SI ∝ T (when Rate of interest is constant) x  ∝ 7 3x ∝ n $\frac{x}{3x} = \frac{7}{n}$ $=> \frac{1}{3}=\frac{7}{n}$ $=> n = 7 \times 3$ n =  21 years   Nithin K ? answered Apr 1 '2018 at 23:24 All Comments

Post your answers here:

Rich Text Editor, message-ans

Editor toolbarsClipboard/Undo Cut Copy Paste Paste as plain text Paste from Word Undo RedoEditing Spell Check As You TypeLinks Link Unlink AnchorInsert Image Math Table Insert Horizontal Line Insert Special CharacterTools MaximizeDocument SourceBasic Styles Bold Italic Strikethrough Remove FormatParagraph Insert/Remove Numbered List Insert/Remove Bulleted List Decrease Indent Increase Indent Block QuoteStylesStylesStylesFormatFormatabout About CKEditor

Press ALT 0 for help

◢Elements path 

Post

Post your comments here:

Message

140 remaining

Post

Cancel