Ricarda earns a $25 allowance each week. how much allowance will she earn after 7 weeks. explain how to use mental math to solve.

25*7=175 dollars

(1)   5*7=35,write down 5 and advance the 3
(2)   2*7=14, 14+3(from step one)=17 write down 7 and advance the 1
(3)   since there is no more digits to do calculations, write down the 1
the answer is 175

(is this the mental math you re talking about?)

1. statement- ca is parallel to db and e is the midpoint of ad reason- given2. statement- reason- alternate interior angles3. statement- de is congruent to ae reason- definition of midpoint4. statement- triangle aec is congruent to triangle deb reason- asa (angle side angle)