Madame curie made some radium in her lab. she used 2/5 kg of the radium in an experiment and had 1 1/4 kg left. how much radium did she have at first?

Madame Curie had kg of radium at the beginning.

Madame Curie used ²/₅ kg for experiment

Radium left = 1¹/₄ kg

Question:

How much radium did she have at first?

The amount of radium that Madame Curie had at first :

= Radium for experiment+ the amount of radium left

we can do the additional if the denominator is the same, if not we need to find a common denominator, in this problem, the common denominator for 5 and 4 is 20, so the equation would be:

we change the mixed fraction into an improper fraction

So, at first, Madame Curie had 1 of radium

Mixed fraction additional

Additional that have sum of 10

Mixed fraction

Keywords: mixed fraction, fraction, additional fraction, additional, common denominator, numerator

the answer is 45 i just did it on oddesy ware

hi! i think the answer is 1/2 : )