Question 1100308
<br>Let x be the number of pairs of the first type.<br>
The number she bought of the second type was 20 more than one-half of that number: (1/2)x+20.<br>
The first type cost $22 a pair; the total cost of them was {{{22(x)}}}.
The second type cost $26 a pair; the total cost of them was {{{26((1/2)x+20)}}}.<br>
The total cost of the first type was 110 more than the total cost of the second type:
{{{22x = 26((1/2)x+20)+110}}}
{{{22x = 13x+520+110}}}
{{{9x = 630}}}
{{{x = 70}}}<br>
She bought 70 pairs of the first type.
The number of pairs of the second type that she bought was (1/2)*70+20 = 55.