Ben said: For every $60 the sixth graders plan to raise, the seventh graders
plan to raise $90. He looks at the principal's thermometers and sees that
$60 is at the same place on the sixth-grade thermometer as $90 is on
the seventh-grade thermometer.
Ben also makes the claim: For every $30 the sixth graders plan to raise,
the seventh graders plan to raise $45.
Do you agree with this claim? Explain your reasoning.​