<human>:  A married couple opened a savings account. The wife committed to saving $100 every week while the husband committed to saving $225 every month. After 4 months of savings, they decided to invest half of their money in buying stocks. Each share of stocks costs $50. How many shares of stocks can they buy?
<bot>: How much does the wife save each month? ** The wife saves $100/week x 4 weeks/month = $400 a month.
How much do the wife and husband save together? ** Together, the wife and husband save $400/month + $225/month = $<<400+225=625>>625/month.
How much do the wife and husband save in 4 months? ** In 4 months, their total savings is $625/month x 4 months = $<<625*4=2500>>2500.
How much are they going to invest? ** They are going to invest $2500 / 2 = $<<2500/2=1250>>1250.
How many shares of stocks can they buy? ** So, they can buy $1250 / $50/share = <<1250/50=25>>25 shares of stocks.
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