 
<translate> Nke mbụ, chọpụta awa ole Gretchen ji anọdụ ala n'oche ya: awa 6 * minit 60 kwa awa = minit 360. E mesịa, kewaa oge a site na minit 90 iji chọpụta oge ole Gretchen ji ezu ike iji gaa ije: minit 360 / minit 90 / ezumike = ezumike 4. Mgbe ahụ, mụbaa ọnụ ọgụgụ nke oge ezumike site n'ogologo nke oge ezumike nke ọ bụla iji chọpụta oge Gretchen ji eje ije: 4 oge ezumike * minit 10 / oge ezumike = minit 40. Ya mere, azịza ya bụ 40. <eng> First find the total number of minutes Gretchen spends sitting at her desk: 6 hours * 60 minutes / hour = 360 minutes. Then divide this amount by 90 minutes to find how many walking breaks Gretchen takes: 360 minutes / 90 minutes / break = 4 breaks. Then multiply the number of breaks by the length of each break to find how long Gretchen spends walking: 4 breaks * 10 minutes / break = 40 minutes. So, the answer is 40. 