BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

Inflation index & Model K mixer

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 85
Joined: Tue Mar 31, 2009 10:58 am
by GmatGreen » Fri Feb 14, 2014 12:12 pm
The inflation index for the year 1989 relative to the year 1970 was 3.56, indicating that, on the average, for each dollar spent in 1970 for goods, $3.56 had to be spent for the same goods in 1989. If the price of a Model K mixer increased precisely according to the inflation index, what was the price of the mixer in 1970?

1) The price of the Model K mixer was $102.40 more in 1989 than in 1970

2) The price of the Model K mixer was $142.40 in 1989
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
User avatar
GMAT Instructor
Posts: 1052
Joined: Fri May 21, 2010 1:30 amFollowed by: 98 members
Thanked: 335 times

by Patrick_GMATFix » Fri Feb 14, 2014 12:36 pm
This is a ratio. Every dollar spent in 1970 corresponds to 3.56 dollars in 1989. So we can express the price of both years in terms of the same variable: p and 3.56p. Data about any relationship between the two prices will result in an equation that has only one variable, and that we can likely solve!

The full solution below is taken from the GMATFix App.

Image

-Patrick
  • Ask me about tutoring.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10392
Joined: Sun Jun 23, 2013 6:38 pmFollowed by: 511 members
Location: Palo Alto, CA
Thanked: 2867 times
GMAT Score:800

by [email protected] » Fri Feb 14, 2014 12:37 pm
Hi GmatGreen,

The prompt for this DS question tells us that if an item cost $X in 1970, then that same item cost (3.56)($X) in 1989. We're asked what the price of a mixer was in 1970; which essentially asks for the value of X.

Fact 1: The price of the mixer was $102.40 MORE in 1989 than in 1970

Combining this info wit what we were given from the prompt, we have:

(3.56)($X) - $X = 102.40

Since this one equation has just one variable, we CAN solve for X (there would be just one solution, so we don't need to do the math).
Fact 1 is SUFFICIENT

Fact 2: The price of the mixer was $142.40 in 1989

Combining this info with what we were given from the prompt, we have:

(3.56)($X) = 142.40

Again, we have one variable and one equation, so we CAN solve for X.
Fact 2 is SUFFICIENT

Final Answer: D

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1