algebra
posted by Anonymous .
The halflife of 234U, uranium234, is 2.52 105 yr. If 97.7% of the uranium in the original sample is present, what length of time (to the nearest thousand years) has elapsed?

.977=e^(.693T/thalf)
take the ln of each side, solve for T 
The halflife of 234U, uranium234, is 2.52 105 yr. If 98.4% of the uranium in the original sample is present, what length of time (to the nearest thousand years) has elapsed?

The halflife of 234U, uranium234, is 2.52 105 yr. If 98.2% of the uranium in the original sample is present, what length of time (to the nearest thousand years) has elapsed