Figure This Math Challenges for Families

Quick Answer:
You decide. If the value of Ruth's ball started at $3,000 and doubled every seven years since 1927, its value in 1997 would be approximately $3,072,000.

Complete Solution:
Suppose Ruth's ball had a value of $3,000 in 1927. If the price doubled in seven years, the ball would be worth $6,000 in 1934. In seven more years, its value would double again.

Year	Value
1927	3000
1934	2 ×3000 = 6000
1941	2 × 2 × 3000 = 2 ² ×3000 = 12,000
1948	2 × 2 × 2 × 3000 = 2 ³ ×3000 = 24,000
1955	2 × 2 × 2 × 2 × 3000 = 2 ⁴ × 3000 = 48,000
...	...
1997	2 ¹⁰ × 3000 = 3,072,000

The year 1997 was 70 years after 1927, so there would be 10 sets of 7 years during that time. By 1997, Ruth's ball would have a value of $3,072,000. Since it would have a greater value than McGwire's in 1997, it would have a greater value in 1999.

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