GMAT: Data sufficiency 12 | Data sufficiency | GMAT | Khan Academy

TL;DR

The video discusses how to solve equations involving ice cream scoops, find the value of xy, and determine if a decimal is greater than or equal to 0.5.

Transcript

We're on problem 55. At a certain picnic each of the guests was served either a single scoop or a double scoop of ice cream. How many of the guests were served a double scoop of ice cream? So let's say that d is the number of guests that were served double scoop and that's what we're trying to figure out. So what are their statements? Statement num... Read More

Key Insights

• 🛟 Problem 55 involves solving an equation with percentages and total scoops to find the number of double scoops served.
• ❓ Problem 56 demonstrates solving an equation with two unknowns, using substitution to find possible values for xy.
• 🛀 Problem 57 shows how considering the rounding of decimals can help determine if they are greater than or equal to 0.5.

Questions & Answers

Q: How can you find the number of guests served a double scoop of ice cream at the picnic?

The number of guests served a double scoop can be found by solving the equation using the information given about the percentage and the total number of scoops of ice cream served.

Q: Can you explain the process of solving the equation for xy?

To solve the equation for xy when given two equations involving x and y, you can use substitution to eliminate one variable and find the possible values of xy.

Q: How do you determine if a decimal is greater than or equal to 0.5?

Rounding the decimal to the nearest tenth or nearest integer can help determine if it is greater than or equal to 0.5, as demonstrated in the video.

Q: Why is statement two alone sufficient to determine if a decimal is greater than or equal to 0.5?

Statement two states that when the decimal is rounded to the nearest integer, the result is 1. Since the smallest number that rounds to 1 is 0.5, this statement alone is enough to determine if the decimal is greater than or equal to 0.5.

Summary & Key Takeaways

• The video explains how to solve an equation involving the number of guests served single and double scoops of ice cream at a picnic.

• It demonstrates how to solve an equation for the value of xy by using substitution.

• It shows how to determine if a decimal is greater than or equal to 0.5 by rounding to the nearest tenth and nearest integer.