document.write( "Question 1149578: The half-life of strontium -90 is 28 years. How much of a 10-g sample will remain after:
\n" ); document.write( "a) 1 year?
\n" ); document.write( "b) 10 years? \n" ); document.write( "

Algebra.Com's Answer #770904 by ikleyn(52803) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "The general formula is\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    M = M0/(2^(t/28)),\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Where M0 is the initial mass;  M is the current (remaining) mass, and \"t\" is time in years.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "So, the answers (and the calculation work) are\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "(a)  M = 10/(2^(1/28)) = 9.755 grams;\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "(b)  M = 10/(2^(10/28)) = 7.807 grams.\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );