Respuesta :

If Lea has given 23 surveys and has to give twice that then 2*23 = 46 which is the total amount needed. Therefore if she has already done 23 out of those 46, then 46-23 is the amount she still has to do. 46-23=23... Lea needs to do 23 more
23 because twice it would be 46 and she already did 23 so another 23 would be left