Celia has budgeted $100 a week for 4 weeks for food, $100 x 4 = $<<100*4=400>>400 worth of food for the month.
She has one monthly cost of $1500 for her rent + $30 for video streaming services + $50 for her cell phone = $<<1500+30+50=1580>>1580 of single monthly costs.
Celia wants to set aside 10% of the $400 + $1580 = $<<400+1580=1980>>1980 for her savings account.
10% of her savings account is .10 x 1980 = $<<.10*1980=198>>198 to add to her savings account.
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