Question 657198
The number is less than {{{30}}}

A multiple of{{{ 5}}}
and the sum of the digit is {{{7}}}....tells us that number is two digit number


if the sum of the digit is {{{7}}}, then digits could be {{{0}}} and {{{7}}},{{{1}}} and {{{6}}}, {{{2}}} and {{{5}}}, {{{3}}} and {{{4}}}

since the number is a multiple of{{{ 5}}}, the digit on place of {{{ones}}} must be {{{ 5}}} or {{{0}}} because only numbers which ends with {{{ 5}}} or {{{0}}} are divisible by {{{5}}}

now, tens could be {{{1}}},{{{2}}},{{{3}}},{{{4}}},{{{6}}}, or {{{7}}}

since the number is less than {{{30}}}, we can eliminate {{{4}}},{{{6}}}, and {{{7}}}

so, the number could be {{{10}}},{{{15}}},{{{20}}}, or {{{25}}}

as you can see, all of them are solutions; all of them are less then {{{30}}} and multiple of{{{ 5}}}