Problem 2

On March 8, 6 children collect 30 tulips for their mother in 10 seconds. How many seconds do 7 children need to collect 140 tulips?
## Problem 2

6 children
30 nails
$10 \mathrm{~s}$
7 children
.210 nails
?s
$1 p$
6 children $\qquad$
30 nails
$10 \mathrm{~s}$
1 child $\qquad$
30 nails $\qquad$ $6 \times 10 s=60 s$ $2 \mathrm{p}$
1 child $\qquad$
1 nail $\qquad$ $\qquad$
$60 \mathrm{~s} : 30=2 \mathrm{~s}$ $2 p$
1 child
140 nails $\qquad$
$140 \times 2 s=280 \mathrm{~s}$
$1 p$
7 children $\qquad$
140 nails
$280 \mathrm{~s} : 7=40 \mathrm{~s}$ $2 p$