The bar graph summarizes the charge, in kilowatt-hours (kWh), a battery received each day for 15 days.The bars show: 0...

1. TRANSLATE the graph structure

First, identify what each axis represents:

• X-axis (horizontal): Charge in kWh - shows different charge levels (0, 8, 9, 11, 16, 23)
• Y-axis (vertical): Number of days - shows how many days each charge occurred (scale 0-7)
• Bar height: Tells us how many days the battery received that particular charge level

2. TRANSLATE what the question asks

The question asks: "For how many of these 15 days did the battery receive a charge of 0 kWh?"

Breaking this down:

• We're looking for how many days (this is the y-axis value)
• For a specific charge level: 0 kWh (this is the x-axis value)
• Action needed: Find the bar at 0 kWh and read its height

3. TRANSLATE the visual information to find the answer

• Locate the bar positioned at 0 kWh on the x-axis (it's the first bar on the left)
• TRANSLATE its height by reading where the top of the bar aligns with the y-axis
• The bar reaches up to 6 on the y-axis

The battery received a charge of 0 kWh for 6 days out of the 15 days.

Why Students Usually Falter on This Problem

Most Common Error Path:

Weak TRANSLATE skill - Axis confusion: Students may confuse which value the question is asking for. They see "0 kWh" in the question and report "0" as the answer, not recognizing that the question asks "how many days" (which requires reading the y-axis value, not the x-axis value).

They read "0 kWh" and think "the answer must be 0" without properly translating what "how many days" means in terms of the graph.

This may lead them to select Choice A (0).

Second Most Common Error:

Poor TRANSLATE execution - Reading wrong bar: Students understand they need to read a bar's height but select the wrong bar. They might:

• Misidentify which bar corresponds to 0 kWh
• Read one of the other bars with height 1 (at 8, 16, or 23 kWh)
• Read the bar at 11 kWh (height 4)

This may lead them to select Choice B (1) if they read bars at 8, 16, or 23 kWh, or Choice C (4) if they read the bar at 11 kWh.

The Bottom Line:

This problem tests whether students can accurately translate between a verbal question and visual graph representation. The key is understanding that "how many days" refers to the bar's height (y-axis), while "charge of 0 kWh" identifies which bar to examine (x-axis). Students must keep track of which axis answers which part of the question.