Lining Them Up

Relevant wiki: Order Theory

Method 1 : Strategy: Draw a diagram.

Letters farther to the right represent taller people.

-„ Gina is taller than Henry but shorter than Jennie: $- H - G - J -$

-„ Ivan is taller than Katie but shorter than Gina: $- K - I - G -$

Gina appears on both lines. Only Jennie is to the right of Gina, so Jennie is the tallest.

Method 2 : Strategy: Use reasoning.

From the first sentence, Jennie is the tallest of the three people named. From the second sentence, Gina is the tallest of the three people named. Since Jennie is taller than Gina, Jennie is the tallest.

$G>H$ , $G<J$ , $I>K$ , $G>I$

$J>G>H$ again $J>G>I>K$

$So,$ $Jennie$ $is$ $the$ $tallest$